Killed kitten before helping her

I found a kitten on the 30th of May 2015 in a drain pipe she had a broken leg I took her out the pipe kept the little one at my house the weekend as the SPCA was closed on the Sunday. I fed her she was week and scared after I fed her was more relaxed and looked happy. As I could not keep the little precious Kitten (name I gave her) I had to take her to the SPCA on the 1st of June 2015. Today the 9th of june 2015 my wife and I went to the SPCA to check up the little one to get told that they \put her to sleep"\""so they killed her\"" and on the 1st of June 2015 they did not even give the little one a fighting chance to live they did not contact me to say this is what they going to do or to even say do you want to come pick her up and you take care of her nothing of that sort was done. So what happened to the moto of we protect and save our animals"""