My child is very sad during walks and afterwards, or maybe I just thin…

My child is very sad during walks and afterwards, or maybe I just think so? In the stroller he doesn't want to walk, only on my hands, observes everything silently and when we enter, immediately go to sleep, and if not then simply looks at everything with a sad gaze. At first I thought he was tired, but it happens even when I take him out for 5 minutes to the store and straight home. He gets cheerful if he talks and distracts him actively, but as if through force smiles. Or am I just overthinking things? My husband also noticed that after walks he is silent.