Hi girls! Looking for advice when switching from combo pill to a POP.

I finished my placebos in my combo pills and then started my POP right after the last day of my placebos. I did get my period during the placebo week. I read that you are supposed to wait 48 hours before trusting that the POP is in full swing. The Sunday of my first POP I did have sex. He DID NOT ejaculate inside of me and I am taking the POP exactly at the same time each day. Am I safe?