The Processes Followed in a Notice period

At our office, if you want to resign from your post, you have to verbally first talk to our boss, and then put it down on mail. I met my boss on the morning of 4th September, to inform her that I want to put down my papers. The notice period during our last appraisal was increased to two months instead of 1 month, and we could risk not getting appraised if we did not agree to this new policy. This new policy for notice period was not even discussed with us, it was just present in the appraisal letters. I agreed to two months of notice period in my meeting on 4th September. My last day was to be 4th November, my boss told me that there would be some tasks that I will have to finish, we discussed the tasks and the meeting was over. Because we don't have an HR at our workplace at the moment, I had to e-mail my boss directly on the 12th of September, with a summary of the meeting, and my official letter of resignation. My e-mail was not responded on until late evening on 25th October, where she acknowledged my resignation and shared another new list of tasks and projects that I need to finish before I leave. I only had 6 full working days to finish these tasks, after which my notice period ends. If i don't do these tasks, my salary can be held back , my official documents and letters could be held. I believe that my company is either trying to not pay me for the last month, or make me work without pay in November (to finish my tasks). Can I take any legal actions ?