I have a crawling sensation, and rashes on my penis, plus the tip of it hurts i didn't have unprotected sex, but i have masturbated recently?

See a dermatologist: Masturbation will not result in any disease. However, you may have an allergic reaction to a lubricant that you may be using. In any event, because of the symptoms you are experiencing, you should see a dermatologist and have the area examined.

Even without: unprotected sex it is possible to get an STD from other exposure. With rashes and discomfort it would be important to be evaluated and treated. Make an appointment with a health care professional as soon as possible.