What Causes Abdominal Pain While On Antibiotics For Streptococcus?

I am having sore throat for past three years. Test revealed streptococcus A. Took many antibiotics as prescribed like amoxycillin, cephodoxime, azythromycin. Also took levocetrizine and montelukast tablets. Symptoms relieved but it reocurred every time.six months before a doctor did endoscopy, barium swallow test and said it was all because of acid reflux. Reports have Gross LPR written. Last one year I have been active in mild sports and workout. But few months back my upper left abdomen was very hurtful. I belched a lot. Also I started having pain in abdomen muscles and other parts of body also whenever they are pressed. My bones also ache whenever pressed I feel very weak sometimes.Doctor did USG which is normal. But I have irregular kind of bowel movement.I am on a strict controlled diet I was on medication esemprazole d, some steroid, Adobe 10 ..for 1 month. Pain relieved but I can feel swelling time to time in left side of abdomen just below my rib and in between my ribs also. I feel somethungs beneath my skin whenever I press espeaciaaly on left side. My bones also ache when pressed. What is happening. And what should I do.?