trouble eating at 6 weeks out

Hi--had my RNY on May 30th--and since I have been "eating" I am having lots of problems--I take my time eating but within 1/2 hr I am running to the bathroom--I may be lactose introlant//cheese is the worse but today the same happened with smooth peanut butter on a whole wheat bread//I have been trying to drink lots of water today but even that is giving me pains and the "runs"-not sure what to try now--any assistance would be greatly apprecitated--if this does not stop tonight I will be on the phone tomorrow to the clinic for help