Can Pregnancy Happen Without Ejaculation?

My boyfriend and I were hooking up and rubbing/ dry humping each other. He
didn't have any clothes on, and i was just wearing small underwear. He didn't
ejaculate, so I'm not sure if I should be worried about pregnancy. I've read in
different places that pre-ejaculatory fluid does or doesn't have sperm in it. He
hadn't ejaculated for days before this, so there definitely wasn't any semen
left in his urethra. I can still get the morning after pill if I need to. Should
I?