When I click on a button I often do not know if the computer received my click or is waiting for me. I do not know whether to click again or not. Is there some way I can tell?
There is! On most browsers it is on the lower left hand corner of your screen. It will typically say something like: Waiting for response from phciraq.org when it has received your click. If you do not see any message that indicates that the computer is waiting for something, then the chances are that it has not registered your click. So click again.