I think Sedif has two separate questions. First one... "What must I do to make our marriage offical in Minnesota, US?"   IF one of you is a US Citizen and resides in Minnesota, then you guys can go to court to make it a official record in US by providing Foreign country marriage certificate. Since you guys are NEPALI, so far, there is nothing you can do. 

For second question, please read all other responses. 

Good Luck