Dr jenice has given you a complete answer. His advice is correct. If you hod your seamen at the time of orgasm, you are closing the path of urethra and will go to bladder.I think this is called retrograde orgasm. As you have seen you have lost 3 years of life by not getting grasm and creating some problem.
In ancient cult, Taoist youa, used to insist on less or no ejaculation but to convert it into mental energy. This is not proved therapy and this can be a full time job of learning taoist yoga kung fu.
Hi: I would not worry too much about harming your health by withholding semen when ejaculating. To the contrary, holding back can be harmful over the long term to your prostate. Besides that, why not enjoy the whole pleasant experience of ejaculating that we men are lucky to have?
As for your other questions, perhaps someone else out there can help answer as they are unrelated to ejaculation.