Cloudflare can take up to 24hrs to start working, but most of the times it takes 15-20 minutes. Feel free to return here from time to time.
Certain hostings such as Bluehost or Siteground offer Cloudflare from cPanel. Sometimes it doesn’t work. If that’s the case with your website, you should disable Cloudflare in your hosting and configure it directly. We offer Cloudflare configuration if you need help with it.
Cloudflare greatly improves load time, but not necessarily PageSpeed. Try to enabling Rocket Loader – it’s not compatible with every website, so you should give it a try and see if it works with yours.
You can also try to pause Cloudflare and check PageSpeed without it: perhaps it did do improvement, but not sufficient enough.
At Hella Fast we do full website speed optimization which includes many things besides Cloudflare.