Sounds likely the drive needs replacement.  If you have not prepared a set of recovery media and made a backup of your data, do that NOW.

See:

www.dell.com/.../Media-backup

Once that's done, run an extended diagnostic on the drive (F12  at powerup).  If you see an error such as 2000-0142, it's time to replace the drive and reload the operating system from the recovery media.

Thanks for your reply , i have already lost all of my data , at some moment i found that disk has disappeared from this pc , then went to disk management and found all of its space allocated as free space , any way ... what i should do ? replace the hard drive ??? or is there any fix ?? also what caused that 

What error code do the diagnostics  return?

How to do the diagnostics ??

to be clear , i think i have lots of bad sectors and i really need to fix that , they causing the labtop to be slow and freezes some time and i cant use programs really well like before like photoshop / illustrator

i use the labtop for work , and i will be very thankful if you can help me :)

Power down the system. Then power it up and [press [F12] then select diagnostics. See here for an example:

https://www.youtube.com/watch?v=WDpvQ3qwy1c&list=PL1RkaknDn7v-Ucth4gt0U3BHVSY7oNkWr&index=11

i did the diagnostics and got for the Hard drive error code 2000-0157