Why am I constantly nauseous? Please help! ?

I have had digestive issues starting back in 2018, just abdominal pain at the belly button, a sharp stabbing feeling. Visited GI and they said I have Non-Alcoholic-Fatty-Liver- Disease (NAFLD) and Barrett’s Esophagus. Beginning in 2019 I became nauseous every day and it is still on going. I have new symptoms now including increased heart rate (from 50bpm to 140bpm) instantly and I being to shake violently. I can not see my GI doctor for another 22 days, so they are giving my zofran to hold me over. This has been a battle since 2018, and I am tired. I need answers, my doctors haven’t found anything yet. I am tired of feeling sick daily. It’s debilitating. I am also not overweight, I am 6’3” 179lbs. I am also only 20 years old. I need help please, any advice or personal experience tips is welcome as far as it is helpful and not stupid like other people saying “you are a hypochondriac.” Thank you.