Hi, I Am A 17 Year Old Female 5'8 110

hi, I am a 17 year old female 5'8 110 pounds, I've always had really bad stomach aches (when I was 5 a doc diagnosed me with strep in my stomach. I'm constantly nauseous so I take 4mg of Ondansetron twice a day, earlier this year I went to the doctor because I lost all appetite and the sight/smell of food would make me throw up, needless to say, the doctor ran tests and never called back for a check up which didn't bother my mom or I because it slowly subsided after 3 weeks, that was end of October beginning of November, now my symptoms have come back and I've started to throw up again when I eat. It usually has long thin white strands in it. I'm not quite sure what's wrong with me and my mom doesn't prefer to go to doctors.