This is a bit personal but I was master bating about a half hour ago and haven’t in a long time. Well now I have a horrible pain in my abdomen worse than cramps. I’m nervous something is wrong. Is this normal?

Doctor can evaluate. Horrible stomach pain usually means something is wrong. Pain can have many causes such as acid reflux, gallstones in gall bladder, spasm of intestines, twisting of ovary, etc... If one has no available personal doctor then one can try a reliable Urgent Care clinic, or the ER. The masturbation might be coincidental (if no pain occurs during repeat masturbation). Masturbation should not cause pain.