My penis twitching

So i've been seeing my doctor for ever. And i'm concerned i have a problem with my prostate. Basically my prostate goes through periods where it feels very achey and senistive. I feel like its infected. If i drink beer i have severe bladder issues. I will go to urinate and once the flow of urine stops, it feels like a leaky hose, where i still feel urin in my penis because its burning like crazy all of a sudden, and feels like i may pass blood but i never have because i contract and squeeze as if to tell my penis stop peeing, and if i'm relaxed. it just burns and nothing would come. So my answer for that was to stop drinking beer. and since stopping that i don't have this severe burning problem. My prostate however still doesn't feel right all the time and my biggest issue still to this date (3yrs and going now) is my penis will not stop twitching! its not painful or anything but whenever i'm standing still, whether i'm waiting in a line or talking to a friend, whenever i'm standing i have this constant twitch, or spasm where i can actually watch my penis shaking, or quivering. the weird thing is it seems to only happen when i'm standing and not moving. And NO believe me i'm not focusing on it or thinking about it, i am not drawing it out. it just happens. and i do my best to ignore it. but when i sit down dierctly on my prostate twitching stops.... it also sometimes decides to twitch when i'm lying down or trying to sleep as well which is very frustrating. I've been tested for a UTI which i thought for sure was my problem. and the test comes back negative. no Uti or std from the tests from my doc. I've looked into candida and i don't think its that either because i had severe stomach issues from that and my stomach has never been better since addressing the candida. wha i believe is something is wrong with my prostate because thats what i massage to try and calm down my twitch because sometimes its really intense twitching. and sometimes its mild twitching. but it is always twitching when i'm standing still and its sooo distracting i can't focus on anything and gets me in a really antsy and bitter and depressed mood! I need help! i feel like i have an enlarged prostate or something, but i'm only 24 and apparently thats just not possible for someone my age. oh and i've had my prostate checked and a camera up my ass as well. and apparently my prostate is good to go!! yay!!! nothing wrong with me but my penis twitches!!! like non stop when i'm standing!!!! does anyone have anything like this??! the doc i'm seeing thinks its all in my head and i just need to stop worrying about it and know that i'm healthy! This just makes me want to strangle him, or curse him with my torment and dare him to say its all in my head again. i keep busy and that does seem to help. but as soon as i stand still or do something that requires some time and to stand, it can be down right unbearable that i stop what i'm doing and go sit down cause thats the only way i feel normal down there. i also think i feel better after bowel movements but nothing has stopped this problem. It may not be killing me....but its definitly ruining my life everyway possible. PLEASE HELP next person i'm writing is doctor OZ.