Last Night I Was About To Have Sex With My

Last night i was about to have sex with my new girlfrend of a few weeks, i was pretty excited up to the point where i grabbed the condom and put it on. I was unable to maintai my erection after the fact. Its only maybe the third time in my life i have been unable to peform.

I am a overthinker, i even made myself sick with overthinking the embarassment afterwards. Is this normal?