You are so young to have all this and I am not sure but you can google this and you might find one thing at a time but please keep searching I am sure there is help if not go to your doctor and see a doc who can go over your medicall stuff with you
If you have not done so you might consider finding an Internist to support your search.
Tammie is right, you are too young to have to face all of this without some sort of help to feel better.
Hard to say but you could get tested for autoimmune diseases. It also sounds like sort of an allergy.
Hmm. I suggest maybe seeing a certified naturopath if you have already seen a medical doctor (which I am assuming you have if you have been diagnosed) because it sounds like they are just diagnosing you and giving you pills for the symptoms, which might not be working well (except for your thyroid) because you have asked this question.
Naturopaths can administer food sensitivity tests, which are essentially allergy tests, but they measure delayed sensitivity reactions (think of a person who cannot eat gluten, they don't go into a full allergic reaction, but after weeks of eating gluten, they will start having digestive issues/feeling tired/eczema/whatever because their body has identified gluten protein as an invader). I don't have any scientific research at hand, but from what I have heard, read, seen and experienced, food sensitivities can cause that sort of autoimmune... inflammation...you speak of.. or makes autoimmune disorders worse/ can cause your body to inflame.
I have never been to one myself, but since you have many ailments, I would suggest it. Not only could they identify any food sensitivities (which have been found to create or make worse, bodily inflammations and mental fogginess) but ultimately help you improve the aspects of your life you've mentioned through suggested lifestyle changes. As an anecdote, I've known people who had various issues you have mentioned, and after cutting out dairy/gluten/soy/nightshade vegetables/yeast containing food/high sugar food (AKA whatever they were sensitive to) there ailments disappeared or at least markedly improved.
I suffer with acne. I have reduced my dairy protein and gluten intake as they are considered the most 'inflammatory' foods (kept fermented dairy though, yogurt, for the probiotics; fermented milk protein is easier to digest, and have banished gluten more or less because my grandmother is gluten intolerant, and she was telling me what her symptoms were and made me realize I might be like her). Things are getting A LOT better, and I feel better. I still consume these proteins, but less often, and I've seen a dramatic difference. But, this is just my two cents. Good luck!