What Causes Muscle Spasms In Stomach With History Of Congestive Heart Failure?

I have a cough. I take water pills for congestive heart failure and I take potassium twice a day. Lately I have been having muscle spasms in my stomach. I have had them in my forearms for a little while. My doctor did blood tests when I asked about the ones in my forearms and he said it was good. Some of the spasms in my stomach are pretty bad. Should I be concerned? I have had my appendix removed.