Every test I’ve had done has come back negative, but I know something is wrong.

I am a 21 year old female who has been having the same alternating issues for nearly a decade now. around 12 to 13 years old I began vomiting constantly at night. The intense nausea would wake me up in the middle of the night nearly every single night for almost 2 years. Told it was just acid reflux and to not eat after 7pm to reduce the amount of food in my stomach, thus alleviating my symptoms. This just resulted in wretching over the toilet bowel and nausea that would not go away. Flash forward to 2 years later and GI symptoms began to appear; Constant diarrhea, stomach pain, nausea, vomiting all in one. Every bowel movement I made was never solid, only liquid. Was told it was just IBS and given more medication that did not work. When I was 18 the doctors finally referred me to get a colonoscopy with an upper GI scope as well. Biopsies were taken, blood work was ran to test for Celiac, Crohns, the whole 9 yards. The only “abnormal” findings were throat and stomach irritation, otherwise I was deemed completely healthy. Thousands of dollars in medical bills and medications over the last 6 years were piling up and I was frustrated. Now at 21 still suffering I finally broke down and went to see another gastroenterologist. I find it hard to tolerate solid food most days, I have to physically drink most of my calories, and have for nearly 3 years now. Swallowing is becoming harder, my appetite is nonexistent. We did another colonoscopy with biopsies, more blood work - everything he could think of. My diagnosis this time being “hemorrhoids, and anal fissures” nothing definitive came from yet another horrible test. When I was told this I finally broke down in his office sobbing wondering what the hell is left. I felt so selfish bawling over being told I was healthy, but I have been suffering for years and no doctor is able to give me an answer or even alleviate my worsening bowel movement/abdominal pain. I have been on anti anxiety/depression medications since I was 15. And if everyone wants to chalk it up to stress or anxiety I would like to know why, just why has nothing helped?. I have no greater stressors in life. I am financially stable, working my dream job, have a healthy relationship with my partner friends and family. I’m tired of hearing the words normal and healthy. I am suffering with no answers in sight. I am at a complete loss as to what to do next.