Postpartum sex?

So I know they say 6 weeks pp is safe to have sex again. I bleed the full 6 weeks with my first baby just had my second and my doctor told me a lot of women bleed for longer with each baby. I’m 4 weeks pp now still bright red blood so I’m starting to wonder if I will bleed past the 6 weeks. I had the easiest birth pushed 3 times didn’t tear at all I don’t hurt one bit.

My question is If your still spotting at 6 weeks do you need to wait longer???? My doctor told me to go ahead at 6 weeks and doesn’t do the pelvic exam until 2 months pp.