RSS Issue

Hello. My RSS doesn’t work! When i click on RSS icon, the link is myblog/feed ! I got this error: Warning: Cannot modify header information – headers already sent by (output started at /home/dragos/public_html/index.php:2) in /home/dragos/public_html/wp-includes/feed-rss2.php on line 8. Anybody know what is the problem? If you need i’ll post here the adress of the RSS! Thanks in advanced!