Hi im wondering if you can catch an std from giving a boy oral sex for a matter of seconds? as im very worried about this.

Low risk, not zero: Oral sex is pretty safe -- the overall chance of STD is a lot lower than with unprotected vaginal or anal sex. But the risk isn't zero. If your male partner is at high risk (e.g. lots of other sex partners), the safe thing is to visit a doctor or clinic for an oral swab for STD testing (primarily for gonorrhea and chlamydia). Good luck.