And that would be your problem. As BronxWench said, logging in with the center login boxes will result in an empty page like the one you're seeing.
The center login boxes are only to be used when signing up and activating your account. After that, you need to use the login boxes in the upper right hand corner. I am almost certain this is stated in the instructions that you get when signing up for the site.
So, what you need to try now, is to log out again, clear cookies and cache, (and in the case of some browsers, shut down and reopen the browser) and then try to log in again using the upper right hand corner login boxes.
But, since you say you changed your password, did you change it to a new password, or did you try to use the same one again? Because if you used the same password again, then that blanks the field and you'll need the archive mods to help you with that.
Willow Darkling, Forum Moderator.