Not really much to worry about. I take it your snake is a male since you said "he". He's only got one thing on his mind this time of year. Sex! Do you female snakes around? I have several male snakes that haven't feed in six weeks. Make sure he has plenty of fresh water. He should start feeding within the next month or so. The year old frozen mice are fine also. But fresher mice are better. Use up the mice that are oldest first.
Hope this helps.
Heres one of my male Nuevo Leon kingsnakes(thayeri) that has not fed this year yet. I took him out of brumation Feb. 26
