I hope this helps, I suffered major chest pains that started in Jan 2011, out of nowhere too and it radiated sometimes to each sides, arms and i was tired and just a general feeling of being unwell. Had emergency trips galore, its not my heart, and xrays showed nothing as well. I did an Upper GI series (chalk test) 3 weeks ago which diagnosed a moderate gastro reflux problem and was put on the creme of the creme they said which is Tecta (pantoprazole magnesium 40mg/daily) Ive been on it since the 28th of this March...after alot of pain and weight loss..Im starting to feel better, my body is a bit tired still but I think Im getting there, no diarhea but constipation is moderate and instestinal prob a little too. I think you need to wait a week or so, maybe then you will see the full benefit of it. I was loosing hope for a bit there, but im slowly climbing I think.
Take heart, Im happy to know Im not alone with this either