My kitten hasn't pooped in 2 days

Hi! So, I found this lovely black kitten with a white belly outside of my house 2 days ago. I cannot tell yet if it is a male or female but I'll just assume it's a she.Her behind still confuses me. Anyway, I gave her a name, Tupsy. She is around the age of 7-8 weeks old. Tupsy is super playful and energetic and loves to eat chicken. I have her plenty of water to keep her hydrated but she still hasn't produced a single drop of urine. She did poop but it was just a mere pellet. Her belly is still big and full since I brought her in but it worries me that she isn't pooping or peeing. What can I do?

Get it to the vet immediately.  You can try stimulating it to see if that will help, but it could be many things keeping it from being able to urinate and poop.

I had the exact problem last fall and winter when Annabel doesn't go outside much at att. I wish id known about olive oil back then cause I used xlax. Human stuff that did little. This year though the olive oil is doing a fine job. I just don't know why she can't poo on her own in the fall and winter. I chalk it up to outside free flowing air vs inside with no cross breeze hence little air movement and while all she does outside is sit for hours in one spot broken up with the occasional walk? The litter box is no problem. So I chalk it up to free flowing air vs inside air all the time.