^ sorry for caps, just wanted to avoid being told how to view all instances of a clip, as I know how to do that; I'm trying to find out where I've already used the same specific piece of clip in a sequence (which is what I understand this pink line I've drawn a circle around to mean)
can you insert the picture you made instead of the way it is now, as an external link to some png file ??
Via the wrench button on the timeline panel choose "Show duplicate frame markers".
This will show markers on the sections of a clip that has been used elsewhere in the SAME sequence. If you want to know which part of a specific clip has been used in another sequence you can copy and paste that other sequence on the end of your current sequence and then the marker will appear on the portion of the clip used.
The pink (can be any color) line are duplicate frames.
Look at the waveform some of them look the same.