My HTC Thunderbolt screen just went dark wtf do i do?

Okay i was in my car outside someones house staking out(long story) n it was hot as ***** so i was sweating profusely while talking to her on the fone n it seems my sweat has gotten into the phone? and cause the screen to black out i can still touch n operate the fone but i cant see anything at all. am i gonna have to buy a new phone? or jus wait till the sweat inside dries up? or is there anything else i could possible do.