This is normal although if you have red bleeding you need to check it out and stop all pelvic activity. I bled a lot during my first pregnancy and my ob put me on "pelvic rest".
There were no blood or blood clot...it was very light red but more pink/white discharge mixer...
But, sex doesn't cause miscarriage right?
It's safe to say there was no red bleeding...
That's for sure....I get very paranoid.
I'm at the point where sex is off limit...lol
Consult your ob about sex; I would definitely abstain till you are bleeding free for at least a week.