First things first - backup all your data and everything of value to external storage. And remember things like browser bookmarks and contact lists. Once you have done this you can relax - a nuisance is not going to turn into a disaster !
Since you have a WD drive you can use the WD Data Lifeguard tools to test your drive, a free download from WD -
Then run the test(s) on your drive. I am not familiar with the WD tools but if there is a short test run that first. If the drive passes that then run the long one. Alternatively you can download the Seagate 'Tools for Windows', again a free download -
Again run the short test and then the long one if it passes the short test. If you want a version that doesn't install on your hard drive then use the Seagate 'Tools for DOS', this creates a self-booting disc or USB stick.
If the drive passes the long test, whichever one you want to use, then it is safe to continue using the hard drive but I would keep your backups up to date ! If it fails any of the tests it is definitely time to consider a replacement drive.