"Administrator" took over my User Account "Claudia"

After customizing my new Dell PC to my needs and of course my User
Account "Claudia", downloading and installing various
programs such as ZoneAlarm, AdAware, Spysweeper and Tweak UI, I restarted.
== Then - instead of seeing my desktop settings, the system logged me in as
Adminstrator.
=== I went to Control Panel, see if I can switch user accounts, but the
user "Claudia" was not there anymore. My Documents under "Claudia" are, but
that's about it.

= How can I return to the previous state, logging on as "Claudia"?

In ,
cloud36 typed:
After customizing my new Dell PC to my needs and of course my User
Account "Claudia", downloading and installing various
programs such as ZoneAlarm, AdAware, Spysweeper and Tweak UI, I
restarted. == Then - instead of seeing my desktop settings, the
system logged me in as Adminstrator.
=== I went to Control Panel, see if I can switch user accounts, but
the user "Claudia" was not there anymore. My Documents under
"Claudia" are, but that's about it.

= How can I return to the previous state, logging on as "Claudia"?

You could do a system restore, but this will remove your tweaks/installs. Do
the event logs show you any errors?