It just messed up a bit, should go back to normal after a while.
You could try deleting your contacts cache[
?] stored on your computer.
Note: Cache is just temporary files which are stored on your computer. Deleting them will do no harm, will
not delete your contacts and may fix your problem.
Windows XP:
Start > Run > Type
%USERPROFILE%\Contacts and click OK. Delete the folder which is named your email address.
Windows Vista:
Start > In the search box type
%USERPROFILE%\Contacts and press enter. Delete the folder which is named your email address.