In the caves is a typical culture clash. The Indians are used to close quarters and having little personal space. The British are used to much more and often consider it an affront if someone invades that space...this is true of most Western societies.
The ladies in the cave are mashed on all sides by the Indians in the cave with them. They, or one of them, becomes overwrought and panics. She actually acuses Dr. Aziz of inappropriate behavior with regard to her person.
Of course, he has done nothing of the sort, but their inability to understand each other due to cultural differences deepens the chasm between them and causes problems later in the book.