I agree with Alx, try and relax and see what your GP says. He may send you for an ultrasound to see things in detail - which would be great! My experience is similar to Alx, when i had a m/c there were very very large clots.. and sorry for being graphic, it looked like clots with 'extras' iykwim. Things that shouldn't have been there (yes i had a good look) - so i'm hoping yours isn't anything to be too concerned about.

I also had bleeding with this pregnancy, on and off up until 16 weeks, and it was similar to what you're describing. I ended up stopping DTD in the first 12 weeks, just to be sure. And i'm due to have bub in 3 weeks! Hope you have a story like mine xxxx