He cam inside of me

He came inside of me on the 5th. I’m kinda upset because we were using the pull out method and he just didn’t pull out! Wth! But anyway I’m due for my period today and I’ve gotten hot flashes all day on and off. I’m wondering if there is a chance at all I could be pregnant? I’ve already had two kids and I would consider myself a fertile mirtle since both my kids are birth control babies