You probably scratched yourself. This happens. What you describe is not std related. NO std's cause anything like that. So, would this be bad? Well, it's not related to an STD so . . . don't know if a common scratch is bad to you or not. Having received oral sex would not result in a scratch on your face. Perhaps someone or something scratched you in your sleep. In the absence of symptoms of an HIV (which you do not have thus far), you do not need to test from the exposure of receiving oral sex.
There is no STD that would cause this phenomenon. This issue appears to be independent of your sexual act, and you should see a doctor at the first opportunity.