Hoookay this might be tmi? Not really but just a warning?

So I started birth control about a week or two ago. I take it around the same time everyday with all my other medications within an hour of each other daily.

Today my partner and I slept together and I haven't checked <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> in a while cause I've been busy. Apparently I'm within my fertile window for the next 4 days.

We didn't use a condom and he didn't pull out. This is our first time doing that and I'm starting to get a little nervous about it.

If I continue to take my pill (I'm stacking my months) will that avoid pregnancy? My parents are super anti-premerital sex and if I was to get pregnant they'd kick me out... Not to mention I'm still a teenager.

So uh what are the chances I hypothetically could get pregnant? And if the possibility I am is high, what should I do that is cheap and doesn't involve my parents?