Important question:
Are you keeping the drive backed up?
If not, better start - and soon.
I would recommend that you NOT use Time Machine. Instead, download CarbonCopyCloner (free) and use it to "dupe" the contents of the internal to an external drive, creating a bootable "clone" of your internal. Boot from the clone just to be sure the backup is good.
If and when the internal fails, it will then be relatively simple to "clone back" the contents of the external to the new internal drive.
You can use a docking station to do your backups, and even boot from if necessary. And - if the internal fails - you should be able to open the back of the MacBook, swap the old drive for the new, and just "boot back up and go..."
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If it was replaced one month ago, take it back for replacement ensuring you have a complete, sound backup.
By the looks of it, the drive's media has experienced bad blocks in excess of the desired minimum. If that's the case, the media is probably damaged in some way. It might never get any worse (noted by the Pre-Fail) but after working with hard drives since they were introduced 20 years ago, I wouldn't trust it.
If this was an Apple Warranty replacement, act quickly. If it's new, most drives come with at least a 12 month warranty.
Problem is, i have an optibay installed in my macbook and in order to bring it in, i have to completely remove the mod and install my superdrive again. I don't want to do that unless i really have to. I live in Belgium, so by law I am entitled to 2 years of warrenty, so if it may crash i can always bring it in. Better backup frequently then! Thanks guys