Check this out: Insertive Penile-Vaginal Intercourse: Risk of infection 4 out of 10.000 exposures, according to CDC: https://www.cdc.gov/hiv/risk/estimates/riskbehaviors.html
I'm no doctor, but in a similiar situation, I'm on my 14th day of PEP, after a condom rupture, and yes, every day has been hard. i guess we can only be strong and wait for the end of treatment, and take the test. I told my mother, who has very understanding, help me to see that the chances of a infection from a single exposure are minimal, and even so, God forbid, there's a chance for infection, the PEP should take care of it, like it does in most cases (80%+ effectiveness, according some studies), i won't tell you to relax.. because i can't either, and i understand, i just can tell you to be strong, and talk to somebody that can understand what are you going through