So today I log in to find out this person's Screen name changed to her name...

So that was kind of odd because she had all this stuff going on with her screen name.

Then I try and look at her display picture and it won't come up....it just stays at that blue head thing.

What's going on?

They may have signed in on a different computer and not had the option set to remember their username and password.  Or they might have signed in using old style Windows Messenger (which doesn't support display pictures) and so would have reset to default

Have you tried just asking the contact?