I do not know about Healthforce. Since you are already feeling very badly, I would start with food grade (on ebay for one place) diatomaceous earth since it does not cause side effects, i.e. "die off." See the cayenne pepper challenge test in the link below before you take DE. That way you will have a before & after, you will know you do, indeed, have parasites and will be able, then with DE, to see the difference as you continue on with the cayenne.
DE is not likely to kill all parasites. It's just a start. Different bugs respond to different paracides.
MHO being vegan isn't necessarily healthy. I have seen some studies on it that indicate it is not. Plus I never forget someone I knew who was a vegan. She always looked so pale & undernourished. I would like to eat vegan because of concern for animals - but my health over theirs. (Sorry moo moos, I feel badly for you, really.
:-( ) Again, mho.
Something is very wrong with the medical testing they are doing (but they are certainly not always infallible) if you have a yellowish tint to your skin, feel awful & your hair is falling out & they can't find anything wrong.
All you can do, really, is attack the major areas: parasites, candida (that's in the links too - how to find it and kill it), mercury & other heavy metal toxicity, liver cleanse. Yellow skin makes me wonder about your liver. But...you don't want to do Liver Flushes until you have majorly killed a lot of bugs or the flushes can make you feel really ill. (Info on that in the links too.)
This is all going to take time and experimentation and you are sometimes going to feel even worse than you do now. Take it slowly but be persistent.