I ADOPTED 2 kittens from the animal shelter 5 days ago.?

1 is very healthy and the other one is not. i was told that they were both 8 weeks but after looking at a bunch of pictures and googleing the heck out of the internet im thinking 1 is more like 7 weeks and the other is just maybe 5 weeks. The 5 week old was fine the first few days and eating regular kitten chow mixed with wet food. now since 2 days ago he will not eat and when he did he had the runs. now he won't eat and when he drinks water he throws up. I CANT AFFORD TO TAKE THEM TO THE VET UNTIL FRIDAY WHEN I GET PAID. i did get him some catmilk but he wont take that either. i tried to do a good thing by getting shelter cats so if anyone can help me out with some advice that would be appreciated. however, i do not need anyone on here trying to berate me for doing what i thought was a good thing. i am a grown woman and i don't appreciate any negative answers. thanks to anyone who can help me with some positive feedback.