my penis size is too small ,its size is about 4cm long in normal and its dameter is so small after erection its size become 10cm only ,so please help me to increase my penis size,i am very dipressed due to this too small size, ....so please plase help me sir how to increase my pennis size ,what are the exercise for increasing my penis size? I masterbate once aweek from last two year..is any problem with this .Now have memory loss and my eyes flickered and i have back pain , i am a software devoloper and i am working 10 hours per day.if the pain is due to over masterbation or my work.......help me sir, now i am 22 years..