My roommate was on a month to month written contract .

The contract states that if they want to leave they have to give 30 days notice and pay the 30 day period even if they leave sooner.

My roommate is threating to take me to small claims court for 4 days rent prorated because they moved out on the 26th of the month .

Does my room mate have a chance ? Surely a written contract would hold them liable ?

My roommate also didn't clean their room or bathroom on moving out and I have Photos to prove it . Wish id didn't let them use the security deposit

Thank you