Co owner wants to stay in Flat with family

We have jointly owned 2BHK flat in mumbai. In the deed agreement, me, my brother & mother are co-owners. We bought this flat by selling 1BHK flat which was owned by my father. He is no more. To pay remaining shortfall, we opted for home loan. Also, I contributed 6 lacs. Now, my mother & brother are not allowing me to enter the flat/stay in the flat. My brother has corrupt plans & he has corrupted my mother's mind also. My mother is senior citizen & widow. She can take advantage of laws for widow senior citizen women. So, she is threatening that she can throw me out of the house legally. She will file fake police case on me. Also, she claims that she can show that she has major share in the flat as major source for purchase of flat came from selling husband's flat. In agreement/share certificate, co-ownership percentage is not mentioned anywhere. I am homeless. I have my wife & 3 months child. I want to stay in the flat. Can I ask for my share in flat. How I can go there.