#1 SQL errors on user creation

[lodp]

When I try to create a new user, I get the following errors:

Warning: mysql_fetch_row(): supplied argument is not a valid MySQL result resource in /home/lodp/domains/****/public_html/txtmob/login.php on line 30
weird error

When I try to log in with made-up credentials (which shouldn't work because there's no user registered), i get the following:

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /home/lodp/domains/onebigtorrent.org/public_html/txtmob/login.php on line 16

Warning: Cannot modify header information - headers already sent by (output started at /home/lodp/domains/onebigtorrent.org/public_html/txtmob/login.php:16) in /home/lodp/domains/onebigtorrent.org/public_html/txtmob/login.php on line 26

What's up with that?