Page loading

Hello good afternoon, so the last 3-4 days I notice that the website has some loading problems, first I was thinking on the origin server and :heavy_check_mark: everything, 600+mb upload 980+mb download, and settings the same nothing was changed, from there I contact the provider so that can make a fiber optic test if any cable is damaged the result from our/my side all was working fine, I notice that the page was not loading or taking up to 15 sec with one tab and I the other tab the page loaded normal 1,2 sec y started to make tests and sometimes its loading fine others not, there is a web called "ping my server " under the test HTTP it was showing normal loadings on others 15 sec and other directly time out… I have a second domain pointing to the same server IP, not registered on cloudflare and accessing from that domain has not giving me one slow loading, but the domain that is passing thru cloudflare servers has problems. Can any one give me some help or does cloudflare have a problem that they need to fix ? What can I do?