Short Self Test Doesn't Complete

I am running a short self-test and it gets to about 90% and doesn’t seem get any further.  The light on the drive is flashing green and it seems to be churning the disk.  I have about 260GB of files - is it normal for the short test to take so long?  It’s been like this for 30m now and nothing else is accessing the drive.

It’s not normal, run the extended test to see if there’s something wrong with the drive.

When I do a short test it churns for a while then I end up on the UI login screen, the drive has not slept in over 24 hours without anything connected to it.

Any ideas?