Light bleeding in third trimester?

I'll be 26 weeks tomorrow, and I had very (VERY) light bleeding this morning. I was super sick yesterday (threw up 7+ times) with a stomach bug (not pregnancy related - my son was sick too). I'm just wondering if anyone else has experienced this/had any suggestions.
I just had a prenatal appointment last week and they found a healthy heartbeat and the uterus was a healthy size - no problems.