What Causes Chronic Low Grade Fever?

I m a 20 year old female & I ve been dealing with a chronic low grade fever for over a year now. It comes and goes, usually around 99.3-100, though in a great while it gets higher and I m tired all the time. Last year I was dealing with (what I though to be) sinusitis. I was having burning headaches, low grade fever, fatigue, congestion, weird smells, & pain behind my left eye. Blood tests showed my white blood cell count was elevated. I was referred to an ENT who did a CT scan (turned out normal) and looked up my nose into my sinuses and said that everything looked normal. I was then told to get my eyes looked at, that trip reveled a slightly elevated eye pressure and blind spots. After a trip back to my nurse practitioner I was referred to a Neurologist. He told me he thought it was Paroxysmal Hemicrania and prescribed me with Indomethocin. That med helped for a little while but the the stabbing headaches came back so they upped my dose, which helped for about a week. I had a follow up with my NP who did more tests (west nile, lymphoma, lukemia, lupus, hiv, hep c, strep, among other infections I can t even remember.. way too many tests) but they all came back normal. She then referred me to a Cardiologist after discussion of a prior pin sided hole in my heart (from 2002), a GI (from history of IBS), as well as a Hematologist (after another blood test showed my white blood cell count had risen some more). In between all these dr visits I had my teeth checked and had to get a cap redone because it was decaying inside. I then went to Hematologist and Cardiologist, both ran tests, all came back normal. The GI said my stomach pain and tenderness was probably caused by the Indomethacin, which may have caused problems with my stomach acid and possibly an ulcer, for the headaches and suggested a lower dosage (which the Neurologist said was a bad idea). My NP told me to call her with all info after I had seen all the specialists, she then suggested I see a Infectious Disease Specialist. But at this point I was just totally fed up with getting no answers, going from dr to dr, and feeling completely miserable all the time. So I stopped going back to the dr and stopped taking all my meds, in hopes that I would possibly feel better. ( I thought that I was just making things worse by loading up up on medication). After about a week of stopping my meds my stabbing headaches were a lot less. I m assuming this is because I got my tooth fixed and stopped taking that Indomethacin (I m pretty sure that just made my headaches worse). Other then that everything is pretty much still the same. I m having fevers almost every day, & after a few hours they break and I get really sweaty. I have occasional stabbing headaches (left side of forehead and behind my left eye. I still have the burning feeling in my forehead and nose when I breath, as well as BRIGHT GREEN BOOGERS! Just a little more history: When I was a lot younger (from about 4-12) I had high fevers all the time (no apparent cause). I did end up at the hospital because my parents couldnt get them to go down but never had a real answer for why they kept happening. I had kidney stones in 2002 which went away and again in 2009, had 2 shock wave treatments and they went away. I was then put on Hydrocloathiazide because my Calcium levels were too high, and last blood test (in April) showed they still were high and my vitamin D levels were low, so my NP told me to start taking vitamins for that. I have also been dealing with IBS for about 2 years. Just looking for a little advice, or suggestions. ANYTHING really at this point. TIA