urgent super urgent.

I need an URGENT foster for a sweet cat I found outside my work yesterday. my student told me there were some cats outside the building. After work, I went to bring some food for the cats and noticed this one was bleeding on its tail. It was very friendly and followed me back into my work. I brought her to the vet but they said they couldn't keep her because there is another cat. I am fostering a dog at the moment so I have two dogs and I am not prepared to take in a cat, can anyone take in this cat while we search for a home! She doesn't have any place to stay in from tonight!