The places you've lived or visited are no longer a defining factor on contracting a parasitic infection anymore in the USA, and doctors just don't "get it".
Other people you've had contact with, clothing you've purchased and worn (also any other textiles you've been in contact with such as towels, bedsheets, mattresses, pillows), hotels you've stayed in, restaurants you've eaten at..... hell even food you've purchased at a supermarket and meals you've prepared yourself. Insects such as mosquitoes and gnats/biting midges, etc, are all likely vectors for transmission of parasitic infections nowadays. Global travelers, global trade, and yes even global warming have all opened up vast superhighways for parasites that were once upon a time only found in far away places to travel here. Deforestation of the Amazon rainforests have disrupted the home where for millions of years at least one species of Mansonella filarial parasite worm species lived and thrived. This worm was historically only spread by biting gnats, sandflies, midges, etc, and was located only in South America. Now it's spread to most Caribbean islands, Central America and supposedly only as far north as southern Mexico, but the official CDC and academia data on that are terribly out of date. A couple of years ago, the University of Oklahoma City set out a bunch of mosquito traps all around bodies of water around the Oklahoma City metropolitan area , looking for mosquitoes carrying West Nile, Zika, Malaria, and such...... and found a strange new microfilarial worm larvae inside the mosquitoes they were unfamiliar with and took the samples to the vector control labs of the Oklahoma state health department where they identified the larvae as that of Mansonella Ozzardi, formerly only thought to be transmissible by members of the small biting flies/gnats insects (Cullicoides species). The CDC told the OK state health officials it was unpossible for this parasite worm to be transmitted via mosquitoes because there was no academic/scientific journal papers or data existing that described such a thing. The CDC also has published a peer reviewed scientific paper describing how parasitic nematodes posses a property known as "adaptive phenotypic plasticity" meaning they can adapt and change rapidly..... faster than ordinary evolution..... when some kind of environmental changes happen to their usual habitat or preferred victim hosts.... in order to survive and continue their own procreation. They adapt, and overcome.... in order to survive. That's what they do.... survive... and that's what they've been doing for millions of years. Our food supply isn't really safe anymore, any biting insect (bedbugs have become epidemic in hotels, mosquitoes and biting gnats/midges are everywhere) can carry horrible infectious parasite diseases, virus pandemics now spread like wildfire across the planet....... even after half a million people have now died, it's incredulous how many braindead ignorant morons still think COVID-19 is a fake virus meant only for political conspiracies. These things boggle my mind that smarter voices are not being listened to or intentionally ignored/dismissed in order to wake up to these problems and put more effort into dealing with them or intelligently prevent them before they get out of control.
Doctors only know what they've been taught in med school and the formal medical system, and outside of that scope of knowledge, they refuse to accept or even consider anything else, and the American medical system has conditioned them to believe that the USA is too goody two shoes, first world clean and perfect to have any kind of third world shithole tropical parasites spreading and causing disease here. They're willfully blinded themselves to such a possibility, partly because of their own hubris, partly because such a thing scares the hell out of them, knowing that they are untrained and unequipped to deal with such a thing. Well, they're going to have to face exactly such a nightmare sooner or later because international travelers are bringing god only know what into the country. Imported goods are also bringing unknown things in too. So much imported foodstuffs come into the country and the the government inspectors who only manage to actually inspect single digit percentages of the total product brought in, have no idea about microscopic parasite eggs or larva hitching a ride on or inside imported foodstuffs. Beef raised on South American land that used to be rainforest? Seafood and watercress, water chestnuts and bamboo shoots imported by the tons from China/Asia? Don't even get me started on Sushi. Freezing doesn't kill all species of worm eggs or larva, it can actually preserve some species for years. Here in America, 80-90% or all raccoons are infected with the raccoon roundworm Baylisascaris Procyonis and one gram of raccoon poop can contain 250,000 microscopic eggs from this species. The eggs can survive for years, decades in the open. Freezing doesn't kill the eggs, soaking them in pure bleach for 24 hours does not kill them. Only heating them above 160degrees Fahrenheit reliably kills them. The CDC officially says any textile materials, carpet or furniture contaminated with these eggs should be incinerated, yeah that's right the CDC's official recommendation is "kill it with fire", because the microscopic eggs can enter humans via breathing them in or inadvertently eating them. 400 of these eggs fit on the head of a pin, and can float around in the air when dried out. In humans these worms cannot mature to reproductive adult stages (or so it is though), but the larvae can wander all around the body causing severe organ damage including the brain and eyes. The raccoon roundworms can grow to adult stage in dogs, and likely in cats too. No known antiworm drug kills them in humans either, they are resistant with the best known treatment being high dose albendazole but only within the first couple weeks after infection, after that all drug treatments are iffy at best. People have died from them, children are especially susceptible. As cute as they are, raccoons have now become deadly dangerous disease spreading vermin across the nation.
Here's one thing you might be able to try to get a doctor to take you seriously and have a better chance at getting formal medical help.... DO NOT use the word "parasite" in any way when speaking to them. Instead use the terminology "visceral larval migrans" (pronounced like "Viss Earl Larval MyGruns"). That's an official medical term which they do understand, and usually will get their attention.