Mysterious stomach problems for over a year now..awful distention..parasites?

For over a year now I've had mysterious stomach issues. Over 3 years ago I had a burning, gnawing stomach pain that was worse on an empty stomach. I had an ultrasound, and was ultimately diagnosed with IBS. I removed gluten from my diet and symptoms disappeared. 2 years ago I took a very stressful job in which I got little and irratic sleep and constantly ate out, I ate very poorly. I drank tons of lattes and sugary coffee drinks to stay awake on top of it. After about 6 months of this, after my job I felt very fatigued..had dizzy spells, awful insomnia, tons of burping, heart palpitations, nausea, intermittent diarrhea and constipation..and occasionally vomiting. I would eat something one day and be fine, and the next be sick. I went to my doctor and she tested me for celiacs, hypothyroidism, I don't even know what else..and ended up telling me no, you have IBS. I read into candida online and decided to cut out all sugar..as well as minimize fruit and avoid carbs. I also took a candida cleanse supplement. After this I felt fantastic. My symptoms for the most part vanished. I went on a trip to California 2 weeks after that. We camped in yosemite, I did walk around barefoot and drink water out of a spiquet in the campground. About 2 weeks after that trip I developed mysterious stomach distention. Randomly one day I woke up and my stomach was 6 inches larger. When this first developed it only lasted for a few days and would vanish. Then it would come around my period. Now it's developed to where it's literally all the time. I have to hide behind baggy oversized clothes. I got allergy tested and they told me I had acid reflux and was allergic to dairy and yeast. I never eat yeast or dairy anymore. I went to a GI doctor and he literally told me and I quote "you're just going to have to figure it out on your own." I'm despret..this is taking over my life. I just want to hide..I have no confidence. I have constant distention and gas. Btw, I am very regular and have bms at least twice everyday. I will do anything to cure myself. I'm only 20 and never go out or anything because of this. I've tried: digestive enzymes, charcoal, ACV, coconut oil, candida cleanse, betaine HCL, magnesium oxide, ..so far charcoal and magnesium oxide help some..I used to see benefits with ACV but not much anymore..I'm currently on a ten day 3x a day regiment of nystatin, as well as I just began the parasite cleanse paragone as of today. I eat according to food combining principles. I eat pineapple upon waking, eggs with garlic and onion an hour later. For lunch it's usually ground turkey with curry powder and a spinach salad. I usually snack on sunflower or almond butter. For dinner I get another source if protein..maybe more eggs, turkey or a Sugar free rice protein powder. I am trying to become competitive in crossfit and I work out 6 days a week. Please, help me. I've been depressed by this for so long. I forgot to mention I developed seborrehic dermatitis a few months ago. It's on my scalp, and has spread to both my ears. Please, help. I feel so alone in this and just want to feel like myself again.