Cramping!

So I have only been TTC for a month. I just came off of the patch birth control in April, and I have been on birth control for about 8 years due to irregular periods.

I had a POS opk on May 25, 26, and 27, and I believe I ovulated on either the 26th or 27th. I have been cramping terribly on my left side for four days now, each day gets a little worse. My CM has been watery also. Am I crazy, or could this be it?! I know it's so early and it sounds insane, but I can't stop thinking about it.