I am so sorry, she died in a home with someone that cared.....RIP little one
if this kitten has been living on its own and eating whatever for awhile, than perhaps the 'new' addition of high calorie cat food was too rich for him, or perhaps he was so hungry he ate wayyy to fast....give small meals and more frequently. if the vomiting has persisted yet than this kitten needs to see a Vet. they become dehydrated really quickly and this is serious. good luck, let us know how it goes....good of you to take in a stray, God knows they need someone to love and care for them ♥