If the password is not encrypted in the mp_users table, then look in mp_Sites and set password format column to 0 and you should be able to login again. Next change your admin account to your real email address so that if you lock yourself out again you can use password recovery. Make sure smtp is working correctly before changing password format to encrypted or hashed also so you can recover/reset your password if you lock yourself out.
Also after changing your password be sure and log out and then login again before making other changes.
Hope it helps,