If you haven't had any kind of sex - oral, vaginal or anal, you can't have herpes, as Derek said.
It could be an allergic reaction to something you used for lube, or it could mean your skin is dry, and you should use lube for masturbation. You should get some lube like astroglide or KY Jelly, don't use lotion or anything that is scented.
If it persists, see your doc.
AJ
to my knowledge, if you did not have any sexual contact with anyone, its pretty unlikely you'll have herpes.