Odd question

Wondering if anyone experiences anything similar. About 1-2 times a month I will wake up out of a dead sleep with stomach cramping and have to use the bathroom. I typically have a pretty large bowel movement that's very liquidy... and my stomach obviously feels much better. It just doesn't seem right to me. I have an upcoming appointment so I'll ask them but it makes me nervous because I have a grandpa that had colon cancer and I automatically fear something's wrong....