Error Code 0142 and 0146; HDD failure? Fix or buy new laptop?

Hello,

I had my laptop (Dell Inspiron 15 Intel N5010) formatted last week due to IDT High Definition Audio Codec error which had made my audio stop working. My laptop (including the audio) seemed to work fine the day it was repaired. But then I installed Kaspersky anti virus and started receiving two kinds of problems:

1) My laptop kept shutting down on its own and restarted. On rebooting it displayed an error msg saying "windows has recovered from an unexpected shutdown"

2) While working on my laptop, suddenly a blue/black screen would appear and the message would be displayed that "This product is covered by one or more of the following patents: US5, 307..."

I ran the diagnostics by clicking F12 while booting the computer. I received error code 0142.

Later, after much effort I was able to uninstall Kaspersky and then run diagnostics again by pressing F12 while booting. The error msg I then received was error 0146 Self Test Log contains previous errors. I also ran the Dell Diagnostics on Dell's website. It ran out of stipulated period of time while running the Smart Short Self Test. I still clicked on the option that continued conducting this test. However, it went on indefinitely and showed no result, hence, I had to cancel it. I can see that when the computer was formatted last week, the person ran the same diagnostic tests on Dell's website. The result was all tests were passed except the Smart Short Self Test which showed result as "indeterminate". 

Now, my question is, does this mean my hard disk is going to fail/crash? As my laptop is not in warranty period, I do not want to face expenses replacing the hard drive of this laptop. I already spent a lot repairing this laptop. I'd rather buy a new laptop. I'm thinking about going in for Acer Aspire E15 15.6" Touchscreen Laptop (2.16 GHz Intel Pentium Quad Core N3530 processor/1 TB HDD/8 GB RAM/Windows 8.1/No Graphics Card) for CAD $500. Please advise whether buying a laptop or repairing the old one would be more cost efficient. Thank-you tons for reading this and answering!