Stressed in the yard aisle

It sounds as though your horse has become a little overwhelmed by everything going on around him, especially when a lot happened at once. Horses can react in different ways to repeated situations:

Habituation: Usually horses get used to different stimuli over time and become increasingly unbothered.

Sensitisation: Sometimes the opposite happens, and the horse becomes more sensitive and more easily startled by different things. This may be what has happened to your horse, where the threshold for triggering flight behaviour has dropped and he reacts more quickly.

What you can do:

Positive moments in the yard aisle: Try to make the time in the yard aisle as positive as possible. Let him eat hay while you get him ready, to create calm and relaxation.

Avoid horses behind: If possible, avoid having other horses behind him until he starts to relax more.

Short, positive sessions: Work in short, positive sessions in the yard aisle and introduce small reward-based training tasks to strengthen your relationship and his sense of security.

With a little time and training, he can hopefully return to his usual calm self. Good luck!