Could you help me on ques tracker problem?

I have this error when trying to use quest tracker:

: Cannot modify header information - headers already sent by (output started at /home/content/24/8458324/html/questcheck.php:1) in /home/content/24/8458324/html/questcheck.php on line 18

Fatal error: Cannot break/continue 1 level in /home/content/24/8458324/html/questcheck.php on line 117