Re: I've never ejaculated during orgasm
Sorry I don't know more about this. Mayoclinic's website says: "Dry orgasm usually isn't harmful, but it can interfere with a man's ability to father a child." Elsewhere people mention blood pressure and thyroid issues being able to cause dry orgasm. It can be a side effect of medication. Are you taking anything?
It seems like it must have something to do with the prostate and/or seminal vesicles. When we're young (mid/early adolescence) ejaculate isn't produced yet because the ejaculatory organs haven't developed, but it seems they should have by now. Have you had your prostate checked? It could be blocked somehow. A urologist could tell you more.
By any chance, do you ride a bicycle? Bicycle seats can cause all sorts of sexual problems in men from the perineal pressure.