Burning stomach and nausea for 6 months??

[Baileyq155]

I have had this terrible burning and extreme nausea for 6 months. I am a healthy active 19 year old female. I am not stressed out before anyone tries to tell me that's what's wrong with me. I have had a cat scan, which was as normal. Blood tests and stool tests all normal. I had an endoscopy and a biopsy and was tested for stomach cancer and h pylori both for negative. I have a breath test scheduled but it's not for over a month. They found gastritis in my endoscopy. This could be what's causing my stomach issues. My stomach is also very very swollen and I'm a skinny person so it's very noticeable. I am so helpless. I have tried acid meds like nexium, Prilosec, dexilant and none helped. I have also tried natural remedies and cutting out dairy but none with fix my burning nauseated tummy. Which feels this way every single day. I do not know what to do and I can barely go to school or work bc of this pain.. Please please someone help me.. I also do not Smoke or take Advil or anything like that. I am on birth control and amitriptiline for migraines. I occasionally drink but hardly at all. Someone help! I've tired everything..