I cannot achieve an erection standing up

Did you quit porn entirely?
If you feel like you have to masturbate, try to do it more slowly and relaxed. You have to fully abstain from the strong grip for your dick. Just use light strokes to start with and give it some time to become better.

 

No man, you are not the only one. I'm young too (22) and have the same problems and i used to masturbate a lot. Young men like us can recover faster than older men, so we have to do no PMO hard mode for at least 3 months or can be more months. You should read "Your Brain On Porn" site to learn more about this PMO problem.
Stay strong and don't give up

 

Its all in your brain mahn.... Believe me.... My condition was worser than you.... I no fapped for 4 days and during the fifth day i got advice from my superhero (thats what i like to call him)from nofap forum that he was also having my same problem and it took him 2 months of nofap to recover.... Thats killed my anxiety.... It gave me power.... And the 4 day nofap gaves me back my libido(You cant maintain errection means you are not getting continuous libido... It is not venous leak dont fall into that trap)... On my fifth day when i was watching a errotic scene from a movie i got a wood and i stood up to check whether i can maintain it or not... Luckly i was able to maintain for 4 min... (To note out a problem... I have to continuesly watch those scenes to maintain my libido to maintain my errection).... I think porn is the culprit as i am only getting libido watching it.... I had tried so many no faps before but anxiety about maintaining errection kills it... Now i can do that because of my advice from my superhero..... So i write this because i would also like to be a superhero for you all

(Sorry for my bad english)