Most likely who’s cum was it

Ok no judging. My boyfriend and I usually use condoms. Last night he forgot them at home so we decided to do the pull out method. He’s not sure if he pulled out in time. There was no semen on me, none on him but there was a small wet spot on the Bed. I was just curious how thick semen normally is ? If it’s possible that could’ve been his wet spot? I’m freaking out because from what I remember (from the one time he’s finished on my boobs) it was thicker and it remained that way until he got a towel.. we’re both adults and are able to care for another baby but we’d like to wait.. and we’re buying a plan b this morning. Just curious what you guys think

Also how accurate is this app? It says I ovulate in 3 days? I don’t really track my ovulation as we usually use condoms so idk how accurate it is