I was told by my doctor while PG with DD to avoid sex during the first trimester after suffering a m/c the previous year at 10 weeks. I don't know if it does actually help but I did end up having a PG that went full term, although I did still get bright red bleeding at 9 weeks but all turned out ok.
This time round I am doing the same thing (avoiding sex during first trimester) & so far no bleeding at all.

Maybe try to avoid the sex for a few more weeks?? I know it can be hard & DH might feel a little neglected but there are other intimate things you can do together without the penetration side of it (sorry if TMI)

I wish you well & send lots of sticky vibes. I hope the bleeding has stopped but if it doesn't I suggest you see a doctor, maybe request an u/s to ease your mind.

Good luck, I really feel for you.....