This kitten sounds like it’s too small to be away from it’s mother. We don’t recommend them leaving her until 8 to 10 weeks old, that way they are eating solid food, and using a litter box. I would put her on wet food, mixed with a little goat’s milk. That is, if you are sure she is able to eat solid food. The pate kind, with no shreds and chunks for her to choke on is best. Provide plenty of fresh water for her too, even though at her age, she may not know what to do with it yet. You can find goat’s milk in the refrigerated milk section of the grocery, or in the baking aisle in cans or powder. The caned is condensed, so add water 1 to 1.
She needs to be kept warm too. If she has a bed, place a heating pad wrapped in a towel or place it under the bed.
The best thing you can do first though, is take her to the vet. They can tell you her age, and check her for parasites (worms) and give you something to treat them. This is when she can start her first round of shots.
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