If you have an external backup drive, as soon as possible save an image of your HDD using the Windows imaging feature or third-party cloning software. If you don't have a backup drive, I would recommend getting one quickly.
Once you have a good backup image, you can try right clicking on the OS drive and select Properties/Tools/Error Checking, and click Check Now. Make sure you've got the backup image first - if the drive is failing, as it appears to be, this process may fix it, but it also may push it over the edge into full failure. If it looks like the process completed and worked, run Sea Tools again and see if you still get failures. If the process doesn't complete or you're still getting Sea Tool failures, you'll want to replace the drive. Hopefully your warranty is still active.
If it passes on the Sea Tool test after the error check, you'll want to actively maintain a current image backup of your OS drive if you decide to continue to use it, as there's no way to tell how long the fix will be good for. Frankly, I would just replace the drive.