It might be that there is stuff 'waiting to be printed' and causing a log-jam.
Try clicking on your screen on start (bottom left icon) then depending on the age of your machine you will see a menu that has either 'control panel' or 'printers and scanners'.
Either way from this you can get to a menu that shows what the printer is actually doing. If you see documents in the list waiting to be printed, click on them and select 'delete' or 'cancel printing'.
If it is a queue that's got stuck, that will cure it and then you can print.