What Causes Lack Of Stiffness In Penis When Erected?

what's happening to me? i seem to be having problems with my penis. I mistakenly tied a band to my penis for about 5 mins and after that i've lost my normal morning erections. In recent days, i've been getting my erections after 6am and it seems soft all the time. I masterbate a lot. Recently, i feel my penis has shrinken. The size is no longer the same in length. What do i do about it? My second problem is, i am feel weak generally, legs are kind of weak when standing and my eyes are not heavy but are becoming a bit dull and blurr. What should i do?