You can't get pregnant during a period, right?

I had sex with my new boyfriend for the first time last Thursday night and he didn't have any condoms, so he went in raw. I wasn't expecting his member to be as long and girthy as it was, so getting it inside me was kind of a painful challenge. Eventually, he go it in though, and he finished inside. After he came and pulled out, I noticed the semen coming out of me was mixed with blood.

I just thought the bleeding was possibly from the outcome of trying to fit his large penis inside me because I've been taking the mini pill (lyza) for 3 days and I wasn't even expecting a period until the next week.

After a while, we tried having sex again later on that night. I started bleeding profusely and feeling sore and crampy from the waist down. So at this point, I'm assuming I've started an early period regardless of the pills or where I am in my cycle apparently. I stopped taking the pills this morning because I don't really like the way they make me feel, and you can't get pregnant during your period, right?