Hard tummy?

sian

Hi all, hoping for similar experiences if I'm honest. I'm 10 weeks 4 days, have my nuchal scan next Weds 9th Dec. I've noticed in the last hour or so my tummy feels quite tight, its not externally hard at all. But its a strange feeling and makes me feel odd. I've had a wipe of brown blood this morning but nothing since (have been waiting for some brown for about 2 weeks now as I was told I have a subchorionic bleeding adjacent to the sac). I think I'm probably just overly worrying due to miscarriage at 8/9 weeks in June. But anyone else had tight feelings suddenly they've never had before??