Help ... Login problems

I simply went away for 2 weeks, and today when I tried to log in I get a request to check my e-mail and click/confirm that the e-mail received is correct.

Having done that (the e-mail address was indeed correct) I get prompted to select a new 'ID' name and apparently can no longer access my old UID. 

How can I get this corrected?

Why do you keep making changes that cause login angst.