Tummy Trouble?

Anyone out there ever have stomach aches where it feels like you are going to have diarreha and your stomach just hurts, kind of like a burning sensation and then when you get to the bathroom nothing happens? What do you do for it? I have drank water, juice, gatorade, sprite, ginger ale, milk , taken vitamins, and even pepto-bismal. Nothing seems to help. I am going to the doctor about this, but just wondered if anyone else has or had this problem and what did you do for it? This happens to me almost on a daily basis and comes out of nowhere. I try to keep a record of what I eat or drink to figure out what triggers this, but so far its not giving me any clues...its just happening at sporatic times. I do have a rather stressful job and I guess stress could cause it, but it even happens when I am not at work. Any idea what it could be? Thanks for any and all suggestions.