Ok, so I’ve read all these thousands of blog posts about speed, but how am I really supposed to know if my site is actually loading slowly or not?
There are test sites where you can test from multiple locations. But also those can be different than real life loading time, so take everything into account.
GT Metrix is a very good tool for that. It will run a test but also give you insight on what to improve and link to more information about each section.