advice needed on new kitten

advice needed on new kitten I was told she was 8 weeks but I susspect she is mch younger then that, she's very small and has difficulty eating food unless its mushed up,as far as u see she's using the litter tray but not drinking much and gets tired after a little exerciee. I saw her siblings advertised on another site saying they were 5 weeks. So not sure if I need to do anything special. I've attached a picture to see what you think

If siblings are 5 weeks, so is she.   Which is of course normally way to young to leave.  8 weeks isnt optimal but is OK.    5?   Just in desperate cases.  So you have been cheated. 

  (I dont see anything on the dark pic, on my so so monitor).

You must be verry mummy to her, she needs it!

As you mush her food, I presume there is a lot of water in it.  If so, she doesnt need to drink much.

Although, not having much energy soon being tired may be a bad sign.  Lets hope it is just worms, as she is surely not dewormed.

What food and drink are you giving her?

Any way, read on, read on, you do have lotsa to do, with her so young.

Continue to report and ask!

Good luck!

The photo is so dark her eye colour isn't obvious, but at 5 weeks kittens eyes are usually changing from blue so she would probably have blue-ish eyes at that age.

Has she seen a vet for worming?  Does she have fleas?  Both can undermine tiny kittens.