It appears to work fine (it contains my home partition for my main machine I daily drive) and I haven’t noticed signs of failure. Not noticeably slow either. I used to boot Windows off of it once upon a time which was incredibly slow to start up, but I haven’t noticed slowness since using it for my home partition for my personal files.
Articles online seem to suggest the life expectancy for an HDD is 5–7 years. Should I be worried? How do I know when to get a new drive?
As others have said, you don’t have to be concerned about anything if you keep good backups. Disk storage at this time is very cheap compared to what it used to be, you could probably find a 5200 RPM 5 TB disk for ~100 dollars USD, or even better, two 2 TB disks which you could configure with software RAID.