I do think that it is the toxins. I had a similar experience and resorted to taking Diatamaceous earth to get me flowing and to get whatever Humaworm may have left behind after my first cleanse. You might want to consider taking fiber. Drinking lots of water is key as well. Maybe not 4L ha! I'm just kidding. You do need a LOT of water throughout humaworm to get the toxins out and keep you moving. I'm sorry you ended up in the e.r. :(.
The thing with Enemas is if you do too many, then your body will rely on the enema to get you moving instead of itself, so I would take a break from those, and pump in the water and find a suitable fiber.
Also, don't be afraid to add in a lot of water. My guess, is if you had not been drinking plenty of water, then drank a ton, that your body was shocked by the toxins that were finally moving....that is only a guess, and I am not a doctor! You could also be feeling sick for not getting those toxins out efficiently enough. Parasites will leave a LOT of toxins that are harmful to your body as they die. So, take it easy, and keep drinking!!