Unprotected sex- No plan b

I’m freaking out right now because I had unprotected sex with this guy about a week ago, and he told me he pulled out. Then five days later he said I should buy plan b because of pre-cum, but I didn’t because I knew it was too late for it to work. Recently I’ve been getting migraines when I didn’t before and I feel nauseous in the morning. Im also getting bloated a lot but I might just be overly paranoid. Am I definitely pregnant? I’m supposed to have my period this Friday and if I don’t get it I’m gonna take a pregnancy test. I’m only 16 and I’m really scared that I might be pregnant because my parents are against me having sex and I don’t know how to get an abortion on my own. I’m hoping I could get some insight from more experienced women because I’m really new to this.