Admin changed to User?

hi there – i recently hired someone to help me do a redesign on my site and now i’m logging in as a “user”, she said she changed the “admin” to my name is all..when i had tried to change it in the past, i couldn’t so my question is…can “admin” be replaced? if not who do i contact to confirm my login in as i want to be in the admin. And how do i confirm that my name is the admin?

thank you!

ps – she explained that the 1st person who set me up didn’t know what they were doing so it should have been changed long ago…