[Help] Amstaff first night away!

Okay so today is our puppies first night away from his mum and siblings, he was great during the day he sniffed everything had fun played with kids etc etc but as the night came and he got fed he became we could say home-sick he didnt eant to play with nobody he was just looking outside and whining i am really fealing bad as i think i am the one that is making this 😭 Any tips or someone who delt with this (Hes sleeping now)

Could he be sick? (We washed him with anti flee ampule today he was shaking but we kept him in towels for 30mins)