slept with a couple where the wife wasn't fully sure... the morning was rough

looking for a sense check on this one. met a couple in toronto last weekend, lovely chat, met for drinks first all proper. wife was a bit quiet but laughing along, husband mostly led the conversation. we went back to theirs and the play itself was actually nice in the moment, she seemed to be enjoying it. next morning the energy was completely different, she was polite but distant, he was overcompensating cheerful. i left with a knot in my stomach feeling like i'd been part of something that wasn't as consensual as it looked at the time. did i miss flags i should have spotted... how do you read a hesitant wife better in future...