I fell asleep last night with a piece of hard candy in my mouth. i suffer from dry mouth. stupid i know but fo i have to worry its stuck somewhere. will it dissolve?

If it wasn't in your mouth when you woke up it was spit out , swallowed, or it dissolved. Hydrate for your dry mouth, since sucking on sugary candies like this put you at a greater risk of developing carious lesions on your teeth.

If you have no symptoms in the morning the piece of hard candy is likely dissolved or in process of being dissolved in the gi tract. Not a good idea in the long run as it places you at risk for aspiration or choking among others.