What you are going through sounds a lot like what I am. I just went through a full stomach panel and am awaiting the results. Some things to consider: S.I.B.O. Small intesting bacterial overgrowth. Smilar to candida but it is an overgrowth of the bacteria in the stomach, instead of fungus in the intestines, like candida is.
Next, reflux. Some reflux you don't feel in the throat, hence no burning feeling. This is called silent reflux. The reflux can cause the gas and bloating in the stomach, which in turn irritates the vagus nerve, causing the anxiety feeling, need to go to the bathroom, etc.
Next, parasites. Many different kinds cause a host of stomach issues. A couple that directly do are Roundworm and Giardia.
Next: H. Pylori.
Next Reactive Hypoglycemia. This happens after you eat, usually with carbs, but I think possibly with any kind of food.
The last thing I can think of, off the top of my head is an Atlas Subluxation. Do you have any neck pain or problems by any chance? Google, "atlas subluxation symptom" and click on the first entry you see. It has a hige list of possible symptoms associated with it. Hope this helps. I know your misery. I look and feel like I'm 9 months pregnant, constantly dizzy, anxious, nauseous, racing heart, lightheaded, major beain fog, etc.
I just thought of this also. A sluggish or fatty liver can cause these things. Manyndifferent things can cause the liver to become burdened, i.e. alcohol, bad eating, but also a Choline deficiency due to the APOE gene mutation. If you have chronic health issues, you should be tested for MTHFR. Make suremyou get a test that also tests for sib-mutations called SNPS. My APOE mutation showed up there. There is an MTHFR Facebook page (rhe one that has the largest amount of members) and the people that run it are very helpful. I had my teseting done through 23andme.com