Hello,I m 18 years old,and I m having server pain above my belly button,and my mouth is constantly filling up with salvia,I am a liver transplant patient,I have bad acid reflux but it seems to only flare up a night time,I prop my head up at night nothing seems to help,I ve taken over the counter acid reducers and everything you think of,this has been the 2nd day this has been going on,I haven t ate very much,I get sour burps. What should I do?