I've Been Experiencing Pain In My Left Ovary When Ever

I've been experiencing pain in my left ovary when ever I get to that time of the month. I haven't thought much of it because I feel that back pain and cramps are normal. But lately I've come to the conclusion that I should consult a doctor because it is becoming difficult to use the restroom. If I am going number two,it feels like something is ready to burst near my ovary region, and if I move a certain way, it feels as though something is pinching the left ovary and a pain just shoots into my armpit.. Any thought of what this could be, and what I should do?