Shortly after executing "sudo apt-get update" in Terminal I ran the remaining updates in the App Center. Once I started with these updates, I changed user accounts (stayed logged in to both). It was functional at first, I got to a new webpage before my entire OS stopped working. I could move my mouse but there would be no response from the computer.
After about 10 minutes waiting I forced computer shutdown manually and when I restarted the computer it stops mid-boot, listing the call trace and summary.
The error message that I'm getting mid-boot is: "Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0, 0)"