I'm 16 I had sex Friday and yesturday Wednesday I went pee and when I go to wipe the is like a thick milky white substance that came of with a little blood what does that mean.

A white vaginal discharge is normal, however, if it is coloured green or yellow and has an odor it is not normal (just so you know for future reference). You say your white discharge with a little blood, could be a slight irritation from sex and not being lubricated enough, the vaginal walls have become abraided. If this worries you, please see your doctor.