Signs of a dying hard drive?

Right now, my internal hard drive is making strange noises. It sounds similar to disk usage, but is quieter, and is slightly higher-pitched. However, the light indicating HDD usage is not blinking indicating usage. Is that a sign that my hard drive is starting to wear out?

Also, everything seems to take slightly slower to load on Windows, even after reformatting, if that could be taken as sign... or that could be just me.

Additional note: my hard drive, along with most of the other components in my computer, are 4 and a half years old.