[cypher]

The cage change has probably just stressed him out, even when it's a change for the better they still need time to adjust, it can take them up to a couple of weeks to get settled in a new cage. Just give him time, keep talking to him quietly while he settles but don't put your hand in the cage unless you have to for food & water just yet.
Do you have a photo of his set up, there maybe some changes that could help.
If the weather has been warm then I wouldn't worry about the appearance of his testicles that's normal.