Some tips to understand if my penis has a serious problem?

[hellcreig]

When my penis is erected and i pull the skin down i have a difficulty in getting it down fully and i feel a little pain.It's hard to describe it exactly so I would appreciate it if someone could give me some online info regarding penis problems.

[Earendil]

It sounds like you have a mild form of phimosis. It's not uncommon at all. A full phimosis means you can't pull back the foreskin at all, neither when erect, nor when flaccid. A partial phimosis means you can't pull it back when you're erect.
Usually, you need to fix a full phimosis surgically because it's not hygienic, and it heightens the risk of certain genital diseases. It's no big deal, actually, I had to undergo such a surgery myself.

With a partial phimosis, or what you describe, there is no direct indication for surgery because you can pull back the foreskin and therefor wash the penis in its entirety. But of course, it's no fun at all if you are having pain.

Just go to your doctor and talk about it with him, he can explain all details.
But don't worry about it, there is no need to.

[Big Al]

For cases of mild phimosis, foreskin stretching exercises like the one found here (http://www.penisadd.com/exercises/foreskin/) will help.