no right?

So I have irregular periods (haven't had one in two months) and I recently started the shot (this monday) well we were messing around and I told him absolutely not to penetrate me but he did and with out a condom I don't know if I should be worried he didn't cum and he was only in there for a second before I flipped my shit on him ( the boy about lost his dick) but idk any chances I could be pregnant? Like at all