My Inspiron 5721 now with windows 10 but started doing this with windows 8.1

It's been making some strange sounds sometimes when I start it up with only the battery it would make a click but not really beeping sound and it wouldn't boot up, since I didn't think the sound was good I immediately took out the battery especially since it sounded electrical.

  I plugged it , put the the battery in again and it would start up no problem, as time went on I had to do this every time. The last few days I have had to leave the battery out and turn it on without battery at all..

I saw on another post that it may be the hard drive so I did what was suggested

 I turned it off unplugged and took out the battery, held down the power button for 20 sec.  Then I plugged it back in and turned it on and tapped the F12 key on start up and nothing happened. doesn't work on my laptop.

But, as I was trying this I didn't have the battery in it and it starting making the clicking noise with it only being on AC.

I have been backing up my files in fear of loosing everythng. and I don't want to turn it off again just to test it in fear of it completely crashing.

Can you tell me if this is my hard drive,  or what test should I do 

I found this on another website

"you can run a hard drive test utility. I usually use Hitachi’s drive fitness test. This test is reliable and easy to use."

Can anyone suggest this or another test I can do without having to turn the computer off?

Thank you