Hmm, I really need a little more info. Is Spike eating and drinking normally? Is he acting normal other than squeaking? Can you tell if he's scratching at himself while he's squeaking? Is he still squeaking or was it just that one time?
My dwarf hammy used to squeak a lot when she had a mite problem. She was very itchy and uncomfortable and she would squeak while she scratched at herself.

She hasn't done it since I put medication on her. If Spike looks sick or abnormal I would definitely take him to a vet. I would just keep a close eye on him and make sure that he's eating, drinking, and doing everything else that he normally does. I think that
dwarf hamsters are much more vocal than regular hamsters. I've heard them squeak at each other at the
pet store. Who knows, maybe he was dreaming LOL.
If he continues to act different than he normally does, I would take him to see a vet.