Am I at risk of being pregnant?

I've been on birth control for the past year and a bit but now I'm off of it due to health reasons and my boyfriend and I are using condoms. The other day we finished with me on top and once he came and I got off of him, there was cum all around the base of his penis, outside of the condom. Did this just happen because I got off of him? And am I at risk of getting pregnant?