I'm really scared, I don't think this is normal....

The past two times me and my boyfriend have had sex, has been really painful. If he doesn't go in all the way, it feels really tight but not painful, but when he goes in deeper like he usually does I get a sharp pain. I get the pain in my ovaries and across. Usually when he goes that deep, it feels amazing. So during the last two times its felt really good but with an awful pain. Sounds weird, but it's the best way I can put it. I'm worried that maybe it's a cyst or something, I am just now ending my period and the past two times have been during my period. So maybe it's just that, but it's never been like this. Before I started my period, I've had to have him go slower and then work is way up to speed but the pain wasn't bad like this. I think I need to go to a doctor. My mind is running towards having a cyst and possibly never having kids and that's all I want in life, is to have a family of my own. I'm so terrified. Has anyone else gone through this? Any help would be much appreciated!