Pregnant on the pill?

So I started using the pill (combined) on the first day of my period. The pamflet says that I'm protected immediately after taking the first pill on the first day of your period.

I had condomless sex 4 days later when my period had stopped. I took a plan b for safety measures (not good for me, I know). I've been bloated and tired lately.

So my question is - could I be pregnant after all of this?

Please help and no judging!❤️