Any Advice?

So after my boyfriend and I have sex or sometimes during sex I start crying uncontrollably and it really bothers me because I can't stop it. I enjoy the sex and I have a fun time while doing it but I haven't understood what could cause me to cry like that almost every time!! It doesn't hurt and it's not like he's doing something wrong it just so happens that I cry I've googled things and I've talked to my mom about it because it's my mom she's my go-to person but I want to know if anyone else has had this problem before. I plan on going to see a lady doctor I just have to find one I like since I have recently moved. I'm just wondering if there's any reasonable explanation for this happening.