if(!$username){
 relogin("Enter your username");
}elsif(!$password){
 relogin("Enter your password");
}
[download]

I really don't know what I was smoking

You still want

if (!$username or !$password) {
    relogin('Username/Password pair not valid');
}
[download]

It stops you from giving too much information to someone who is trying to break in (eg. Ok I have the username right now just work on the password)

another hint

my $sth = $dbh->prepare("SELECT * FROM info WHERE pword='$password'");
$sth->execute() or die "Couldnt do it: $!\n"
[download]

This will fail if the MD5'd password has a ' in it. Just imagine what that SQL will look like when the $password is expanded. You can use placeholders to get around this

my $sth = $dbh->prepare('SELECT * FROM info WHERE pword=?');
$sth->execute($password) or die "Couldnt do it: $!\n"
[download]

DBI will properly escape any characters that need to be escaped