I got diagnosed with Irritable Bowel syndrome about a year ago.

I was really stressed out all the time and I started feeling car sick/bus sick, and my stomach was unsettled in general, among other things. (I thought I was lactose intolerant for a while.)

They gave me these pills that cleared it up fairly quickly, so if it is the same thing, with different symptoms, I highly recommend trying the drugs. Worked wonders for me.