If your HDD is clicking, it is definitely time to buy a new HDD to replace it, ensure that it is of a similar make, so it can fit inside your laptop. If you get this HDD as soon as possible, you can replace the current one, and get any files off of it before it is too late.
The clicking sound basically means that your HDD is failing and dying, and that is probably the most common way of telling that you HDD is on its way out. Also known as the "Click of Death".
https://www.ifixit.com/Answers/View/26988/Any+one+know+how+to+fix+clicking+noise
That can explain how to get some of the data off of it if it is still on there.
If your laptop is in warranty, contact the manufacturer and they should offer to replace it for you.