Some plan b problem and relation advise please

I had sex with a boy and he gave me a creampie which it was my first time and it wasn’t planned. Im not on birth control bc Im too scare of the side effects and i have been on the IUD which wasn’t confortable for my mind lets just say that. He bought me a plan b he was sorry bc in the moment i told him to do it you know “ the moment” but life is beautiful...... I took the plan b but after taking it we didn’t again just that he came on my mouth and i swallow, this happened 2 weeks before my period 1 week and 2 days after my ovulation period. Sooo since it was my first time taking it with an actual load inside me plus my ovulation already passed I was like im going to be fine, my cervical fluids are not liquid they where white like a paste im in the save window right. A week after i took the pill, meaning today 4/8/21 im waiting for my period and nothing has happened and im starting to be on denial, im in the what if situation. The day i took the pill i slept a lot that day and the following days i was feeling pelvic pain and the sensation that my period was coming. My question is has anyone of you girls experience something like missing a cycle and then getting your period the next month or something like missing your period for x amount of days and then getting it bc it would be the first time something like this happen to me most of the time i took it was a pull out scare and my period would be there a days earlier or the same day i was expecting it.

Also should i tell him or should i wait more days, he is treating me weird lately i dont know how to talk through text to boys and i feel so nervous when we call he so calm and my the opposite of that it scares me so much cuz idk what he thinks about me or if he really like me or not. He is loving and romantic but when it comes to text or call he is sooo dry and serious 😓😭