Don’t understand ERROR?!

Hey,

I’ve been getting this error on a few different occasions. First I was getting one when I tried to log in and it seemed to be a problem with my theme (Japanese Cherry Blossoms)So I changed the name of my theme temporarily so I could log in. It worked. Then I changed back to the theme and it works, except that now I just tried to activate a plugin and got this error:

Warning: Cannot modify header information – headers already sent by (output started at /home/britwit/public_html/dirtndiamonds/wp-content/themes/jap-cherry/functions.php:2) in /home/britwit/public_html/dirtndiamonds/wp-includes/pluggable.php on line 865

Warning: Cannot modify header information – headers already sent by (output started at /home/britwit/public_html/dirtndiamonds/wp-content/themes/jap-cherry/functions.php:2) in /home/britwit/public_html/dirtndiamonds/wp-includes/pluggable.php on line 865

The previous error also read “cannot modify header information” but referenced other lines of code.

Any idea what I can do to fix it? Is it just the theme? I love the theme and would love to find a way to use it.

Thanks