Vultr hosted site does not connect after setting up Cloudflare

I’ve just set up Cloudflare for my site (stumpgrinder.info), which is hosting a rocket.chat instance (stumpgrinder.info:3000). Since setting up Cloudflare, the site is inaccessible. I have an A entry in the DNS directing to the IP address, and a CNAME, both automatically set up by Cloudflare. I am absolutely stumped, and I have no idea where to even begin looking to try to fix it.

Cloudflare does not proxy port 3000. Cloudflare is HTTP/S only over a set of generally used ports.