Considering getting copper iud advice plzz

So I’ve had the nexplanon implant for 1.5 years and have had non stop periods so figured my body probably can’t handle the hormones, my biggest fear of the copper IUD is pain/ bleeding during sex, I’m on the smaller side of humans and my boyfriend hits the back of my cervix during sex(sorry for tmi lol) just wondering if this will cause issues with my iud placement and cause extra pain, also concerned that people say their periods last 3 weeks, I can handle the extra flow and cramping, but i can’t do a long period again, also any experience with excessive bloating?