Torture in notice period

I am currently serving notice period and they are assigning more task and expecting to work for more hours than regular hours. I am thinking to not to work beyond my timings so will it create any problems while relieving? Will the manager have capability of adding comments or any such things on my experience ketter or anything or they can postpone my LWD by any chance ? Please suggest as I have stuck in the same organisation for 5 years.