I'm worried because my penis is very itchy but only by my balls. help please, what do you suggest?

Here are some ...: Without a direct look and feel on the lesion, it's hard to give an accurate Dx although it may present a patch of psoriasis, lichen planus, etc. Clinically, gingerly applying topical 1% hydrocortisone or flourinated steroid cream once daily for 3-10 days will most likely ease the itching, not for cure. Long-term use of steroid cream may induce skin atrophy; so, beware. More specifics? See urologis

Agree with Dr Lin: I find adding menthol cream with the hydrocortisone helps as well, but see your dermatologist or urologist if not improving.