How early in the day did she start panting?
I just though of this- She may have had such an interest in the oil because it would have been cool, so she may have been hot and looking for something to cool her off.
It looks like she is broody but also very overheated. Can you bring her somewhere air conditioned, or find some way to cool her off quickly? Also, I have read that ACV in water can limit the absorption of some nutrients that are needed on hot days, so I would recommend supplying a supplementary...