I'm not a physician and I don't know how your procedure was performed, but if the surgeon left your seminal vesicles intact, I believe it would be possible for you to produce some ejaculate.   My understanding is that the seminal vesicles typically are removed along with the prostate, just in case any cancer cells may have migrated to them.   Of course, many post-op patients find they ejaculate a bit of urine, but that's hardly "semen like" <g>.   That's great that you're able to have a satisfactory erection. I'm still waiting, but getting by with a VED (the "pump").   Best wishes to you!