Probably a silly question but I have read that plan b one step does and doesn’t prevent implantation.. anyone know the real answer?

Had our “whoops” on Tuesday night... I believe I ovulated Monday night due to the ovulation pains I had but my app said highest chance was Tuesday and said ovulation day. If I did release an egg Monday night then my chances of getting pregnant from Tuesday night are probably pretty high right?

It’s now Friday morning and I’m wondering if it’s too late to take plan b one step... if fertilization occurred then will it prevent implanting?

Thanks!