I’m scared that I could be pregnant

So I’m 16 and I am NOT ready for a child anytime soon. Me and my boyfriend had sex 4 days before my period was supposed to start according to eve, and we didn’t use protection. I am on the pill and no he didn’t pull out. I didn’t orgasm and I think I pushed a good amount out. I took a My Way I think 2 days after this and eve said I had only a 3% chance of pregnancy. I’m a day late and I have terrible anxiety. What are your thoughts. My boyfriend and best friend keep telling me everything is going to be okay and to calm down and I’m not pregnant. I’m just super scared and I need advice.

Also me and my boyfriend ALWAYS use condoms it just ended up being spontaneous and we literally didn’t have condoms around. So please don’t shame me he’s only came in me one other time and I also took a My Way then and I wasn’t as stressed as I am now and I don’t know why. I’m scared out of my mind.

Update:

I’m 4 days late, but I’m actually not nearly as stressed as I was before thanks to everyone’s input, I’m just hoping it was the emergency contraceptive messing with my period, does anyone know how long they can delay your period?