What Causes Left Abdominal Pain With History Of Ectopic Pregnancy?

I had my left Fallopian tube removed in October 2014 due to an ectopic pregnancy. I have had 2 periods since then and now started what I think is a period, but according to my average I was 9 days late. I have also taken pregnancy tests and they have all said negative. But now I am having extreme pain on my left side where I had pain with my ectopic pain. What could this be from and could it possibly be from my left ovary failing to release an egg?