It looks like the Apache web server is not running. Could you check if just starting it using the above command brings your site back online?:
sudo /opt/bitnami/ctlscript.sh start apache
Unfortunately, I'm unable to figure out what caused it to stop, since the Apache error log is empty due to the log rotation. Could you uncompress the latest rotated log file and see if it contains any hint about why it stopped?
gunzip -c /opt/bitnami/apache2/logs/error_log-20190520.gz