Is what happened—the contamination of personal belongings such as the mobile phone and keys, and the resulting contamination of hair, comb, and place—considered a delusion (waswas)?

The questioner, a sister, is afflicted with obsessive doubts regarding purity. Since her sister informed them that her hands were wet with water when she placed the bag in the purse, this means that the wetness they found was water and not impurity. The default state of things is purity. If they doubt whether it is water or impurity, the default is purity. They can purify those items by washing what can be washed and wiping what would be damaged by washing until the substance of the impurity is removed.