Questionable and Complicated

My boyfriend and I were fooling around yesterday, and we didn't have sex at all, didn't even attempt to haha. But he placed his penis on the outside of my vagina and basically was just pressing up against me, and if any barely went inside, and when i say barely i mean not even actually press more than just the tip in but not even that, more just like pressing up against me, if you could say? But I was just wondering if there is any chance that I could be pregnant from precum, because of course we don't know if he released any, but he didn't release any *** at all. So is there even a chance of pregnancy? I've been having white discharge, and few hours later i had a lot actually, but I'm due to have my period either tomorrow or in the next couple days I think...so should I worry at all?

Ps. We've decided we are not doing this again, skip the worry.