Suggest Treatment For Abdominal Pain With A History Of Kidney Removal

I went to the doctor today because I had a kidney removed a year ago and I'm having bad cramping the area from my side to my belly button. And because I have alot of stress on me, from various things going on in my life.

So he prescribed me ranitidine 150mg and carbamazepine 200mg, which from what I can tell is a heartburn medication and a seizure medication. I'm afraid to spend the $ to get these filled and waste the money if they don't help me because I've never had a seizure or heartburn.

What should I do?