How do i recover a deactivated administrator account on windows xp

I was borrowing a computer, windows xp.

I needed downloading privelages to use with my online college, and so I was trying to be polite when I made a second admin account. I have done this many many times on other pc's and never had a problem with having more than one admin account. I cannot simply figure out why when I made the new one....it made the old one dissapear. I would rather not have to tell them I broke it, So please help me resolve this asap. Everyone says go to the switch users screen and press ctr+alt+delete twice. I did, in fact numerous times. No box pops up, nothing happens etc. I need HELP please. E-mail Michealgeorge85@gmail.com Save me. please.