Cramps... (Not really sure how to ask this but I'll go for it) lol

Tiffany
So this passed week was my fertile/ovulation week. And the week before that I had my period. But my period was very very light almost spotting. And it didn't last as long as normal. Well I'm sufering from cramps right now and I'm just wonder what the cause could be... It's just cramps on my lower abdomen. 
Please help. And thanks in advance