Chances of pregnancy

So 2 days ago I had sex which I rarely do only a 2nd time I was drinking we didn’t use a condom We stopped literally after 1 minute or less of him being inside he didn’t even ejaculate. I took a plan B maybe 16 hours after just in case. Think there is a really low chance of becoming pregnant? I was worried rhe next dat because my friend told me about precum even tho its a really low chance of pregnancy. I rarley have sex I know it was dumb to not use protection but shit happens. Plus I changed my mind a minute after.