Help!

Can precum get you pregnant? I had sex last week with my boyfriend for the first time properly and we've been having it for the past week without using a condom. He didn't cum in me and he's convinced he didn't precum in me but my period is late by 3 days. My period is usually regular and I'm starting to get concerned. Am I just being paranoid? Please someone help reassure me. I've got sore boobs and mood swings like I do when I'm on my period and the cravings but still no period 😣