My son is British citizen but I’m not..my husband me and son cam to Pakistan on a visit ..but here …

My son is British citizen but I’m not..my husband me and son cam to Pakistan on a visit ..but here my husband don’t take care of me andmy son at all and don’t give money for living ..I’m at my parents..he used to do domestic violence and mentally and emotionally tortured me but I was bearing everything for my child..I’m pregnant nw also and he knows about it but not doing effort to bring me back home..my son is not well here..I want to go back to U.K. For my children further and health..he has all my nad son travel documents and he is not giving me dem..how can I go back nw plz help ..