Why is my kitten being so retarded? She wont quit running and attacking!?

Ever since my poodle died today she has not let me get up! When she went to my room she went under the bed. I went in there and when a stepped on my rug she tried to hiss and jumped out to attack! Please hel[p me get her to stop. If losing my dog means this i want the dog to come back as a ghost.