Mini schnauzer behaving strange, stand in middle of room and stares at nothing, lost his mojo

by Chantelle
(Sydney)

My 11mth old mini is just not himself. His behavior has changed overnight. He hasn't got much energy, is eating well but very dull and almost sad. He will stop mid walk in the middle of the room and stare into space all dazed and confused. He was on antibiotics and anti hestamine for itchy paws/skin but they didn't seem to indicate that these were side effects. I've stopped giving him the tablets now but I'm seriously concerned that something else is up. He also doesn't want to be with us and keeps heading off to be alone. No play biting anymore and no energy or inclination (I'm not sure which one) for runs. Can anyone perhaps shed some light?