I had spotting at pretty much the exact same stage of pregnancy as you. 16 weeks and 5 days... I freaked out as we'd gone through so much to get pregnant and stay pregnant and I wasn't feeling a lot of movement at that point in time.

I went in to see my OB (luckily I'd taken the day off work before this happened - I was simply exhausted) and she did a scan and checked my cervix and all was well. We never discovered a cause for the bleed and I didn't have another episode and Samuel will be 4 weeks old on Friday.

Please call your OB and get checked out if you are worried. They'd rather you come in for nothing than stay at home and stress and find out later that something was wrong.

BW