Sex related questions [NSFW kind of]

Hey guys,lately I've been thinking about my sexual experience so far, and it brought up few questions that I can't seem to figure out. Decided to post it here, as I don't feel comfortable enough discussing gay sex related things with anyone else, as I do with fellow gay people. I guess there is no not-awkward way to talk about it for me, so I will just write it plain and simple.I noticed something interesting when I was having some fun time with myself, that I: 1) grab my penis quite hard, which creates pressure that is not quite possible to receive while having ordinary sex; 2) I did it really fast. Without those two things, it wasn't quite it. Back in a day, I would take anti-depressants, and I believe that due to that, I then had a really hard time comming while masturbating. It simply took like 20-30 minutes for me to get off. Now, I don't take them any more but I believe that is where the habbit of masturbating fast with a strong grip comes from, which now is kind of annoying. Do you have any experience with such obstacle? Right now, to do quite the contrary, I usually masturbate with as gentle grip as it is possible - strong enough to just move the skin up and down, and I do it as slow as possible, which makes it quite a long mission for me to come.Another thing that I noticed, which is fucking annoying as hell - when I have some fun time with somebody else, they are giving me a blow-job or a hand-job (most of my experiences narrow down just to those two) I can't come. To the point, where I jack off, get close - they take it in their hand or mouth and I instantly don't feel like coming anymore. That is totally bizarre and just to be sure, it isn't because I'm not attracted to that person (I definitely am), but for whatever the reason I can't come while they do it to me. Do you think it is some type of psychological blockade or something? Because once I take it in my hand again, I immediately feel like coming again.I am sorry if I am too forward and somewhat rude, but I couldn't find a better way to ask all that without it being straight forward.I would appreciate any type of input regarding those questions of mine, or maybe share some of your experiences or problems and we might figure something out together :)Cheers!