I have no clue what to do. I have 8 baby chick's that are around 3 weeks old. Today I noticed one that was off in the corner by itself. I picked it up and it went kind of limp in my hand. I laid it back down and it did get up and walk but very slowly away. I see no injurys on it or anything like that. Also I see that with each breath it takes it's tail feathers are moving. it was fine lastnight and today it just wants to sleep. I know something is really wrong but I am new at this chicken thing and have no clue what is going on. There feed is medicated chick food. not sure if that matters but I am lost as to what could be wrong or what to do. please help me.