Upgrade & New Install Problems

I had a site that I had an old version of Word Press, where I was using it just for a blog. I decided to go all the way with Word Press, and upgraded the blog, and did a new install for the rest of the site. I went with a theme called Beautiful Sunrise, and was getting an error message. I continued to change and add pages, however, https://www.nkinn.net was showing up, but I got an error with https://nkinn.net. When I changed it in the Settings, I could get only one or the other, and I was trying to get them both to display. Now I just get an error message, and it will not allow me to go in to the administration panel and log in. I tried to re-upload the files on the server, but that didn’t work. I tried to “upgrade” but then it told me that Word Press was installed, and there was no upgrade. What can I do to fix this? The only message that I get when I try to log in is:

Warning: Cannot modify header information – headers already sent by (output started at /home/nkinn/public_html/wp-content/themes/beautiful-sunrise-10/functions.php:72) in /home/nkinn/public_html/wp-login.php on line 202

Warning: Cannot modify header information – headers already sent by (output started at /home/nkinn/public_html/wp-content/themes/beautiful-sunrise-10/functions.php:72) in /home/nkinn/public_html/wp-login.php on line 214

Warning: Cannot modify header information – headers already sent by (output started at /home/nkinn/public_html/wp-content/themes/beautiful-sunrise-10/functions.php:72) in /home/nkinn/public_html/wp-includes/pluggable.php on line 557

Warning: Cannot modify header information – headers already sent by (output started at /home/nkinn/public_html/wp-content/themes/beautiful-sunrise-10/functions.php:72) in /home/nkinn/public_html/wp-includes/pluggable.php on line 694

To view the site, https://www.nkinn.net works, but https://nkinn.net does not.