Salary issue

Hi, I was in to project management for an Delhi based agency for hotels disk marketing.on 3rd July I had word with my senior about my dad's health and on that very same day I resigned. He said he'll be needing 1 month time, however I've asked him to make it for 14 days or so since I'll move after that. On what he said that will try. Now on 12th I got to salary cheque and on 13th I've have asked him again to get the hand over prices started as 14th would be last working day of mine. Well he simply rejected that by saying that I've to serve the notice period at any cost otherwise I won't get the paperwork. I was even ok with that and for 15days salary I was also ok not to take. However he and the HR were forcing me to stay there otherwise exiting for me would be difficult. On this I took my laptop and mobile and handed it over to HR. Saying that I won't take any paperwork or July month's 15 days salary. Also I'm ready to work from home if it's required. Now what they did is they cancelled my June month cheque too which was there in bank to get clear. Please let me know if a company can cancel a cheque on such situation of previous month salary. Also can a company ask employees to work more than 12 hrs here. Please help me in this