concerning the plan B pill..

Okay guys, so I know most have us have all been here. And fortunately, this is my first time on this train. So, my boyfriend and I recently had jntercourse. He happened to come inside of me... It was a lot of cum and very deep. Mind you, I am not on birth control but did take 1 plan b pill about an hour after it happened. So, pretty much what I'm getting to is could I get pregnant? Is that possible? I've also haven't started my period yet and my stomach has felt a little boated and I've been pretty gassy. Anything helps, literally just super curious!