Back in October, I started experiencing the sensation that something was stuck in my throat, and a burning sensation in my esophagus.  Started on 20mg Omeprazole, and Carafate.  Did not help, so I had an EGD done.  The Dr. said he saw no reflux, and that everything looked fine.  A couple of days later the sensation of something in my throat came back.   Several months before I had been continually hoarse and did not know why.  I went to and ENT doc, who put a scope up my nose and down into my throat, and he said I had damage from reflux, which caused the dry sensation in my throat.  We upped the Omeprazole dosage to 40mg, and after a few weeks I was fine, and even stopped the medication.  Everything was fine until the beginning of June.  I started having constipation and diarreah for about a week, and I got this pressure in my chest with a sharp pain just below my sternum.  The bowel movements seemed to go back to normal, but the pain stayed.  It feels just like some thing is poking me in the sternum.  Very uncomfortable.  Went back to the dr. and he put me on Aciphex 20 mg, which seemed to help.  It only hurt if I skipped a pill, but I still always felt like there was something wrong in my sternum.  I recently had a colonoscopy, which they said was normal, so they chalked up my pain to IBS.  I was feeling fine until the colonoscopy prep.  Ever since then,  the pain in my sternum has increased again, and I feel a burning sensation in my esophagus, and slightly in my throat.  The Aciphex doesn't seem to be working.  I am afraid this is something more serious that they are not finding and I'm scared.  Any input would be appreciated.                 

ETA: I also went to the ER one night because it was so bad I thought I was having a heart attack. They did an EKG, chest X-ray, and abdominal ultrasound, and said everything was normal.