When logging in from a computer in lab, I received a log-in error that said, "That username does not exist." I tried to enter my username and password twice on the log-in page, each time receiving the same error, and couldn't get it to work, but when I tried to enter it on the index, it worked. ???
My guess is that the connection to the database was down when you happened to enter it in the first two times. Anyway, your username obviously exists, so I'll lock this now. :P