constant heart palpitation

Hi I'm a 20 year old male and I've been having about 100 or so palps a day for the last 2 months or so. They usually occur after I'm done eating something. I also get a shortness of breath during and after I eat for a few hours. I have gone to the doctor to have an x-ray, stress test, ekgs, blood tests, and a holter monitor.

The doctor did mention that everything is all right, and that if I am still worried about it, I could do a 30 day monitor. He also prescribed omeprazole, saying that it could be because of stomach acids. I've been taking it for a week now and I haven't really seen any improvements at all. The palps have just been really bothering me since nothing I do seems to be helping at all.

Thanks for any help!