Have you called the vet to see about this?
I would call and ask them how long is too long for your kitty to not be going. Do you see her at the litter box straining or trying to go?
That is odd for a vet to say without other advice...
If you haven't found her straining or going someplace else then I would suggest trying the plain pumpkin as Handsome Kitty suggested. I've never used the olive oil but have seen it suggested and work for tiny kittens that are constipated.
The other thing I would suggest is a second opinion with another vet.
I am worried about her even cant sleep for that ... vet is also not helpfull even i paid them but all in vain may be my pali is in problum how can i sort out it