Breach of Contract?

I am a college instructor here in manila. I'm planning to submit my resignation letter stating that i can no longer work after the pre final exam due to my in'law's condition. She's the one taking care of my daughter when I'm at work.I don't think I can still commit, I have frequent absences bacause of this. Will it be possible for them to file a case (breach of contract) against me (April 5 is supposedly my last day) even if I submitted my resignation letter 2 weeks prior to its effectivity date? or should I still follow the 30-days rule? What if it's emergency? Thank you and Godbless.