[Always *]

Well, it does sound like he scratched you if nothing else. You could have been scratched and had your period. It's not unusual to have short periods, especially when you are young. If you otherwise feel fine, I wouldn't worry to much, especially considering that you're young. That said, you can always talk to your doctor or other health care provider about it.

You should talk to your boyfriend about being more gentle as well. Even if the blood was your period, him pleasuring you shouldn't cause you undue pain.