How to restore other user account? urgent!!!!

Hello, my other user account on my comp. is lost and I don't know why, I just made new user account and I used my old user account and i stand by the computer cause I ate lunch then when I came back i turn on the comp. the nmy new account was opened and then I clicked switch accounts and my old account was lost. then I clicked my comp. (folder) and all the files are there but in the my doc. (folder) all the files were lost. please help me! or only the my doc. (folder) on my other user account to my new user account. please i really need you're help. faster!!!