small amount of discharge no photo!!

I'm 31 weeks 4 days today after peeing when I looked at the toilet paper there was the smallest amount of what looked like whitish yellow discharge.. i freaked and thought maybe it was part of my mucus plug? It wasn't a lot and hasn't happened again. Anyone else have this happen? Do I need to freak out or is this normal? Not having any contractions baby has been moving today normally... I just need some reassurance! Thanks