one week old call duckling appears to be having seizures folding his neck down and cant stand, keeps going backwards. He has some sort of problem with his eye and has been scratching it. I put some vet rx on his bill and in his mouth. I want to give tetracyclin but can't figure out how to mix it to a gallon. his neck is kind of bulging on one side like his muscle is tense. And it's Saturday so no vet to call. PLEASE HELP!