Photoshop can tell you how long you are spending on different commands as you work. To find out (if you really want to know how long you play with each toy, I mean tool), then click on the right-facing triangle at the bottom of the document window. Usually you will see document info here, such as the file size but when you click on the triangle, choose Show from the menu and then choose Timing. This is effectively a stop-watch which times your actions on each tool or command.
So now you can start working towards your personal best, painting a circle in under 0.5 seconds.