Talk to Gynecologist on Heavy And Painful Menstruation

I got my periods 3 weeks ago and they are very heavy and painful which is not normal for diagnosis the doctor said that my endometrium lining is 16mm which is way too asked me to go for d&c.i am very much confused and nervous about from which doctor i should get d&c as it is a sensitive procedure and i dont wanna get into trouble after the procedure.

P.S : married from 10 years but couldnt a history of PCOS, infertility and right now i dont have any other issue apart from thickened endometrium. I am planning to go for IUI but before that i have to get everything right. please guide me.