Lower abdominal pain and mid-cycle bleeding?

[katzone]

Last night I had an awful pain in my lower right stomach, felt like I had strained a muscle. I have it again today along with some spotting but I am mid-cycle. I have had a google and all I can find it ovulation pain/bleed but I am on the pill... I shouldn't be ovulating lol!!
Anyone have an idea? I think I might go docs, I had a mid-cycle bleed last month too but no pain.