We've made an easy way to check this: The Testy.me Status Tracker.
If the status tracker is reporting everything is okay, but you are having problems, then it might be a problem on your end. Chances are, it'll probably be something we can't do much about, and you'd be best talking to a professional near you for help, but you can always contact us if you think we can.
If the status tracker is reporting that something is wrong, that's a problem on our end. Don't worry - we get instantly notified if something isn't right and we get working on getting everything back up straight away.