Hmm, before I delete your account, try to mess around with your privacy settings, they can sometimes block cookies that are required to log in to sites.
Here's how to access the settings:
Tools > Internet Options > Privacy tab
Lower the level of privacy security and see if you can get back in.
If that doesn't work, make sure your password is correct.
If the problem still occurs, I suppose deleting your account will be the quickest option.