Kitties can certainly get into things (string especially) that can cause blockages. I am glad you are separating your kitties, I think it will give you some idea of what is going on.
14+kitties mentioned the vaccine. It is quite possible your kitty may have a reaction to the needle. It take Sweet Pea and Snowball
, a couple of days to get over a vaccine.
Cat maid to:
Puddles, female Himalayan (16 yrs)
Jasper, male Ragdoll ?? (approx 9 yrs)
Sweet Pea, female silver tabby DSH (approx 7 yrs)
Rose semi feral, a cpietra rescue, female tabby (approx 6 yrs)
Snowball RIP (1991-2005)
In a cat's eye, all things belong to cats.-English Proverb
“While we are free to choose our actions, we are not free to choose the consequences of our actions.” Stephen R. Covey