Gilly won't go

It was very warm tonight, but I grabbed Gilly and took him to the arena anyway. My foot is still colorful and sore, so I didn't want to have to use stirrups. And Gilly was dripping sweat, so I rode bareback. Danged if I could not get him to move. We'd do circles, then a few steps, then barely a lap, then stop. So I thought I'd try the pasture since the other horses aren't around to bother us. But he still didn't want to move. A flock of starlings took off and he turned into a whirling dervish. He did a full circle and a half, then stopped dead in his tracks. I persisted and got him to take me back to the arena where we did half a lap and I gave up.

Maybe I need spurs.