Glad you decided to rescue this little kitten, she probably wouldn’t have survived without your help!
Sounds like she is doing fine, but I understand your worry. Since she is still very young and most kittens aren’t fully weaned until around 8 to 10 weeks, you can get some goat’s milk to supplement her diet. You can get fresh in the refrigerated milk section of the grocery, or in the baking aisle in cans (it’s condensed so add water 1 to 1) or powdered (which I prefer) and just add water according to directions. I mix up about a cup at a time and keep it stored in the refrigerator. Put a little in a saucer and warm in the microwave for about 10 seconds to take off the chill. Give it to her that way or pour a little over her wet food. It will give her added probiotics and hydration too.
I don’t know what could be making her not as active. You could call the vet and ask them what they think. If she is pooping and peeing and eating, I can’t think what it could be. If, after the worm medication she wasn’t pooping, I would be concerned that she had a large worm burden and maybe had an obstruction. Her eyes are clear, no runny nose and eyes and sneezing, then she could just be missing her littermates. Just give her extra attention, pets, and chin scritches. Make sure when she uses the litterbox that she doesn’t injest the litter if you are using clumping litter, as some kittens tend to eat it and will get a blockage from it. Keep us posted on your girl!
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