The neck will probably benefit from some work, but this sort of joint always benefits from being left a few days to let the timber acclimatise and settle down. It may improve slightly, it may get worse or it may stay the same. But you are best deciding what to do once it's in a stable condition.

You'll want to use a set square to check the neck heel, and probably make up some small right angles from card to check inside the neck pocket. If something's out of true, it helps to know exactly which part.