If you could ejaculate before and now you can't you should probably talk to your doctor.

You didn't say how old you are, or if you have had ejaculate in the past. Ejaculation and orgasm are two seperate physiological functions that just happen to take place at the same time in men. It is possible to orgasm and not ejaculate, and it is possible to ejaculate and not orgasm.

Things to keep in mind to tell your doctor if and when you go see him, were you injured in some way before this happened or did you start on some kind of medication.