OK I'm not sure if this is an STD or not. A girl I'm seeing (we have not had sex/oral intercourse yet) and I were messing around a week ago. I was fingering her for around 20 minutes. I started feeling small 'chunks'. I wasn't sure what it was so I kept going. When we were done I went to wash my hands and there was some type of hardened white/yellow material on my hand, almost like snot. It peeled off. After she was gone I checked my bed sheets and there were little hardened balls of it on the bed and what looked like white powder. I know this sounds really weird but I've never experienced anything like this before. It sounds gross but it honestly reminded me of crusty mucus. It's wet/liquid then dried to a crust.
What is this?