OK whne you went "click" you should have looked at the volt meter and seen if it went down to ) or turned on the dome light and seen if it went clear out, if so, it would mean you were not getting enough voltage.
If not, then it likely would be a bad starter or the relay.
Clean the ground cables, esp the other end where it grounds from the battery and where there is one from the engine to the frame, clean that and the connections on the starter.
If it does it again grab your hammer you carry and crawl under it and beat on the case of the starter and see if that helps.