As far as I'm concerned there's no justification for his behavior other than possibly a lack of knowledge. Demand better treatment next time.

Next time, you come before he gets inside. Especially without experience coming from intercourse might not happen--but there are also hands and tongue, a gentleman does not leave his partner unsatisfied!

In the early days of our relationship there were some times she didn't come because she was too shy to accept a hand down there, but after that initial time of learning there's been only a few times in our 16 years together that she hasn't come and those have always been due to something interfering.