Diarrhea for 3,5 months. Help

Hi,first: I visited couple of different doctors. Age: 28 male. When it started: 3,5 months ago How: When I started drinking home made kefir fermented in unpasteurized unboiled cows milk (my dad was bringing me that milk and forgot to say to boil it) Initial symptoms: Diarrhea 5-6 times a day, not completely watery but very wet. Explode-y. I was drinking kefir for couple of weeks, and then stopped.Thought my digestive system.was cleaning and it was normal.I was wrong.I stopped drinking it. Tests done: Serology, stool tests,blood tests. Everything was ok,except: Low vitamin D, high Calprotectin value (500 normal is under 50), H. Pylori infection. Tests done: Gastroenterologist - colonoscopy,endoscopy. They found GERD, lvl 1-2 internal hemmorrhoids, stomach dysplasia? No biopsy was done. Colonoscopy was done 1 month after endoscopy,during that time I took internal supplements to get rid od H.Pylori because gastroenterologist did not want to treat it,supposedly it is normal. I did not believie him so I got rid of it. Done H pylori test after a month and it came negative, also Caprotectin values were under 50. Doctor suspected initially crohns or ulcerotic col, but with test he dismissed them. Visited Alergologist after tests above: Tests: Allergy and celiac blood tests, lactose breathing tests. Everything was negative. He suspects IBS, perhaps even undeveloped IBD despite what gastroenetrologist said previously. Next tests done: Gut imbalance and parasite stool tests. All negative. Current symptoms: Diarrhea 1-4 times a day. Almost never normal stool since problems first started. Diarrhea after eating raw onion, very fatty food, most of the time milk products, spicy (have not eaten it since i have problems,had only few times something very mild), sometimes raw garlic. I get reaction within 20 mins after eating food. Sometimes any food. Sometimes I get times when I do not have diarrhea but constipation. These days and reactions are sometimes unpredictable. I have better and worse gut days. Please,what could it be? Thanks