What happens when a contract is breached?

Short story: I was charged with a crime, prosecutor's plea deal promised a guidance of 90 days' jail, but the DA actually recommended 96. Is this breach of contract? What happens immediately?

It's been less than 6 years, so the statute of limitations hasn't expired. TIA.
This can't be breach of contract as:
- it was human being negotiated/recommended, not agreed
- it wasn't a negotiation between you and the prosecutor, but them and the state and,
- the Judge ultimately decides so no contract is made - it's a ruling - and that you could appeal if you felt it was wrong, but not underneath breach of contract, and for a better reason than just that you felt it be wrong.