He's not aware of leaning in any particular direction at first, merely tries to stay on. He can feel himself slipping to one side, rights himself, slips to the other one. Then his brain tells him to stop being a jessie, he has feet in the stirrups and hands on the reins and all he has to do is pull, yes?

He pulls. Too hard, probably and Duncan doesn't like it but he does stop, not far from the stable.

'You bloody idiot.'

It is unclear whether he's talking to himself or the horse. He doesn't stop to decide which either, he's pulling his fags out because he needs one to calm his racing heart.