Sorry, I really didn't know what to title this! I'm hoping someone will be able to offer some advice.
I know a man... Ahem... Who has an issue with his penis. He's only very recently become sexually active so I'm not sure that he'd ever realised that this isn't normal. The problem is that he cannot achieve a complete erection, only ever getting part way, and I suspect this may be because his foreskin won't pull back away from the head- it gets completely stuck and just won't move at all and he finds it painful.
He won't go and get medical advice 
but I'm worried about what other effects this might be having, I think he's having some psychological issues that may be related, not that he'd admit it, but I'm also worried that it might cause some real medical issues- what do you all think?