Dell Inspiron n4020 - read internal hard drive failure

Good evening to everyone

I'm in panic!
My laptop was purchased about a year ago, it has never fallen to the ground, been exposed to crazy temperatures. I treat it carefully.

Yesterday all was ok and today when I tried to start it, it appeared the message "read internal hard drive failure" and I have no idea what to do, if it's fixable or any other option.

It was purchased in Hangzhou, China which makes it hard to : a) read the manuals clearly; b) get assistance from where I bought it.

Please, if any of you kind souls knows how or what to do, let me know... I'm really worried!
I have all the papers, cd's and the drivers...
Just need a clue or guidance as to what to do next.

Thank you
Ana