no.
Yes, the ejaculation (semen coming out) doesn't occur immediately after the erection. It usually requires some additional stimulation for an ejaculation - such as the one provided by intercourse.
Keep your mind on something completely non sexual, although do not get to extreme and loose your hard, just keep your mind partially in a different place and you will be able to hold out longer.
Yes, if you press against the spot between your testicles and anus(gouche) you will feel it but no semen will come out. I do not think its healthy because it builds up inside you and becomes...very thick If you are talking about leaking from the vagina, there is no way to stop it unless you use a tampon afterward. It is normal for semen to leak out after sex in the case of female. If you are a male, it cannot be stopped either as a few drops come out of the urethra and that is perfectly normal also. It can be wiped off with a Kleenex or toilet paper.
clench, hold, or grasp
Yes, hotels can typically hold your luggage for you during your stay.
athletes don't hold their breath during the 100m they hold their breath during the 50m race so they don't have to waste time breathing.
during
to release your hold on something
release
For some people they can't and they just go out and do it. For others they simulate intercourse & oral. And for some they just have "sex fantasies."
Yes, movers can hold your belongings during a move if you arrange for storage services with them.
== == First of all, you can't stick a sperm inside you with your finger. The least amount of semen that you can hold on your finger contains millions of sperms. Though fertilization of the ovum needs millions and millions of sperms, and also depending on their motility, It is possible to get pregnant this way. It has very low probability, but could happen.