Like Rolo1234 has said you may be burnt out, have you started to study yet? If you do feel like this, take a step back from studying and just have a day of relaxing. It might help you to get back into your "A-game" as they say.
It's currently January, you do have plenty of time to study so try not to worry about the future etc.
You're welcome to PM me if you need any advice/have a question