I have the same - found on u/s at 6w. I was taking aspirin and was meant to start clexane for a clotting disorder I have. This was stopped by the OB.

I had no bleeding until 10w when I had reddish spotting on wiping for about an hour. U/S was fine and *alf* was measuring to dates and bouncing around happily. Like Mum of 5, I am also a nurse and after a busy shift on Friday I had more bleeding (brownish this time lasting for an hour) and some cramping. This has settled so now I am just taking it easy and trying to remain calm and positive.