I know it is a silly (probably stupid) question but should i go?

Of course you should go- but don't stay too late. Force yourself- tell yourself, I'm going to go home, and I'm going to sleep good, and I'm NOT going to drink. That way you go home to rest well for your important cl, and you aren't hung over. It might be tempting to have a little drink, but put a tight rubber band on your wrist. Every time you think about drinking, snap the rubber band onto your wrist. (Bring extra rubber bands in case the other breaks.) Good luck, and Happy Birthday (almost)!