Anxious about possible pregnancy + discharge questions

don't really know how to start this but I sort of have loads of questions. First off, my boyfriend cannot finish while having sex. He hasn't been able to with any of his past partners and we'd have sex over 10 times and still no luck. I'm 18 so i'm trying to avoid pregnancy, so this isn't a huge deal to me now just because he can't finish so him finishing inside of me isn't really possible. Because of this, we started having unprotected sex and maybe have like 4 times now. Each time he has not finished, but I know that precum exists and this is my main concern. I know it's possible to get pregnant by precum but we are unsure. I tend to worry and get anxious so now I have a small fear I could be pregnant. My predicted ovulation was 4 days ago and we have had sex the whole week before up until the day before ovulation. Today he fingered me and when he took his fingers out there was heavy discharge. It was stretchy and creamy and somewhat cloudy. I'm not familiar with discharge so i don't know if this is normal or not. Also I've also had really bad headaches, i have a feeling of being super hungry, super stressed, so i'm just wondering if you all think there's any possibility I could be pregnant, and if the discharge is normal at this point in my cycle?

Also, my period isn't due for 10 days, so Id have to wait a while before taking a test.