Nervous Wreck

My boyfriend and I just started having sex a while ago. Our first time was the day I ended my period on November 4 (Tuesday). We would use condoms and everything was good until November 8 (Saturday) when the condom broke and he came inside of me. We immidiatley went to go buy the Plan B pill, and as a relief I got my period again a week after on November 12 (Wednesday) and lasted all the way up to Sunday. On Saturday, we did not have intercourse but we were fooling around and he came on the outside parts of my vagina (I had a tampon in, so I don't think anything could have gotten in). On Sunday night, we had unprotected  sex using the pull-out method and he did not ejaculate neither in me nor on me, although there was definite some precum. (I considered it to still be a "period day" since I was bleeding a bit in the morning but was clean at night). I said I wouldn't worry about some sperm finding it's way into my eggs because apparently my ovulation is not for another few days. Today, we had protected sex and the condom did not fail us, but few minutes afterward, he put it in again for about 1 or 2 minutes without protection, but did not end up coming at all the second time. I am worried if some semen he still had on his thing although dry may have still had sperm that found its way to my eggs. The thing that worries me is that I'm 17 and pregnancy is not an option for me. Maybe I am overstressing but if anyone thinks there is a big risk I would like to know about it before it's too late...