VN7 791G78B2 Performance Issues/Drive Error

For the last couple of weeks I have been having performance issues on my laptop. The disk usage would go up to 100% (this had been going on for a while, but not as persistently and not being that much of an issue) and the laptop would become extremely slow. I would have to wait a long while for anything to open. But this is not just specific to the 100% disk usage because sometimes even when it's low, the performance would be affected. After trying to google the problem a few times (and trying to turn off Windows Search and other fixes for disk usage that didn't work) I came across a post that said deleting Bitdefender fixed his/her problem. Now I had just renewed my Bitdefender subscription a couple of days earlier and did not want the money to go to waste (and my bandwidth is limited so I did not want to have to re-download if deleting didn't fix the issue) so I contacted Bitdefender about this to see if there's a way around uninstalling. After sending them an "autoruns log" and another Bitdefender specific log, their technicians suggested that I run chkdsk, then after that System File Checker and DISM command. They said it could be the beginning of a hard-drive failure because \Device\Harddisk0\DR0, has a bad block. Bitdefender does not seem to be causing the issue.

The problem here is that chkdsk (both offline AND online) keeps getting stuck so I cannot complete it. It would go on normally for the first 10-20 minutes, then it would reach a point about 1/4 of the way (or 8% in the offline version) where it would stop advancing and the estimated time keeps getting higher and higher. When I leave it overnight the estimated time would reach 19-20 hours. I need my laptop every day so I cannot really wait more than the 9-10 hours that I leave it during the night. According to some forums I checked out, it's not even supposed to take that long in Windows 10. The laptop is practically unusable because of how slow it becomes during online chkdsk, so to properly use it I'd have to stop it. And I have been waiting for a day where I do not need it so I can run the process for longer than that, but I'm really worried about what this could mean until then. I did not try System file checker and DISM yet, because the bitdefender technicians seemed to specifically suggest that I need to complete chkdsk first.

Unplugging the laptop seems to fix this problem temporarily. When I unplug, whatever had been clogging the performance seems to clear up after a few seconds. After it does, I plug it back in and the issue would only resurface about an hour later. I can play games like Witcher 3 and Overwatch normally, even if the issue is ongoing.

Another thing that has been happening along with this issue is notifications to (1) Scan Drive Errors (which I try and gets stuck; I get this notification very often, especially after I unplug the laptop and the performance clears up) and (2) to update virus protection whenever I turn on the laptop, even though Bitdefender is up to date. This kinda makes me suspicious of Bitdefender again, so I will try to uninstall soon if it really could cause such massive performance and drive issues, although that seems unlikely.

My laptop is 2 years old; I did not expect to be facing such issues this fast. I paid a lot of money for it and I really can't afford a new laptop any time soon. I'm very worried and I'd be extremely grateful for any input about this.

Note: I'm posting this a second time as my initial post doesn't seem to appear in the forums