if someone leaves you to cool your heels, they force you to wait, often until you become calmer.
The youths were left to cool their heels overnight in a police cell.
cool (one's) heels
To wait, sometimes so that one becomes calmer or more composed. You need to cool your heels for a minute and stop yelling at the staff—they didn't do anything wrong.We were excited, but we had to cool our heels when the release date for the new game got pushed back.
cool your heels
be kept waiting.
A British variant of this is kick your heels .
ˌcool your ˈheels
(informal) be kept waiting: The bank manager had asked to see her at four o’clock but she had to sit cooling her heels for almost 45 minutes.