Getting Redirects and Comment Error

I went to respond to a comment on my blog and got the error below. Now I also cannot access the page where the comment is and the page redirects to google.

THE ERROR:
Warning: preg_match(): Delimiter must not be alphanumeric or backslash in /home/oakhurstkitchen/oakhurstkitchen.com/wp-content/plugins/semalt/semalt.php on line 59 Warning: Cannot modify header information – headers already sent by (output started at /home/oakhurstkitchen/oakhurstkitchen.com/wp-content/plugins/semalt/semalt.php:59) in /home/oakhurstkitchen/oakhurstkitchen.com/wp-includes/pluggable.php on line 1178

THE PAGE:
http://oakhurstkitchen.com/banana-rum-breakfast-cake/

RELATED ISSUE?
https://wordpress.org/support/topic/latest-update-caused-major-site-issues

Please assist!

https://wordpress.org/plugins/semalt/