Should I stay in my job or look for another job?

Ended my recent contract, asked for a pay raise. Pay wise was agreed upon and 1y contract was signed. However in recent weeks, I have been doing many OT and it doesn’t seem that it will die down. In fact my boss told me I will do more OT with him. Since there is no OT pay (only meal allowance), felt that my pay isn’t worth doing that much OT. Thought of leaving halfway if keep doing OT (but feel guilty because I am in the middle of a project) but 1y is too much to wait till end of contract