What to do my husband is forcing me to sign on sal e agreement of flat

I am living in LIG flat(in my husband's name) with my husband and 2 sons. I am working central government employee but my husband is not having any job for the last 2 years. I have a flat in my name only. My husband made the cash down payments and EMI of the home loan were made from his salary account though I gave all my pay to him from the very first month since my marriage but he intentionally did so. At present there is no outstanding loan on that flat. My husband has property papers of that flat. Now he is asking me to sign the sale agreement papers of that flat so on sale of that flat he can keep all the money. He is telling me that I donot have any right for that flat as on records he made all the payments from his salary account. 1. Do I have any right on that flat. 2. May I sale that flat on my own and purchase the adjoining flat in my name. I am Sikh by birth. My husband is Hindu. We had court marriage in 1996.