It hurts when i masturbate, why?!

Yeah, You need to use Lube, The Friction of when you Masturbate eventually causes the skin on your Penis to "Peel" basically, The more you don't use lube, The more cuts that will begin to form on the skin, making it really hurt if you don't use Lube. Just Lay off the Masturbation for 2 - 3 days and let it heal. Use Lube next time after that.

It happened to me before.

That's chafing.

Abstain from self-love for a few days to allow the tissue to heal.

When you're ready for action again, maybe loosen up your grip, and use lube. If you use a two-handed or fingertip-heavy technique, change to a one-handed grip technique. Use a firm but not clenching grip strength. This should prevent future chafing.

Getting a girlfriend (or boyfriend if you swing that way) is also a good idea. Sex is better with a partner and you'll get a lot less chafing. If a partner is not available, your frequency in pleasuring yourself is fine, just don't squeeze it dry in the process.

Enjoy your penis.

Because the skin is peeling.

Quit washing your penis with soap or body wash and tou wont have dry penis skin.

Use dove moisturizing bar.

You need lube possibly, also depends on how long you go for creating more friction. Maybe try a different technique.

You're doing it dry. Use lube and it won't happen.

Maybe you need a mouth..