In troubleshooting this more, I found a post that said to look in the wp-config.php file and look for any extra whitespace before or after the php tags. I didnt find any.
So then using my backup (following the upgrade directions is VERY IMPORTANT) I placed my old wp-config.php file back in my root directory and I am in. Everything so far seems to be working fine. As for the other warnings, I havent encountered them yet but I will continue to test this and post my findings here.