When you rub your eye vigorously, the delicate tissues of the eye can become irritated and result in a sensation of bruising. Rubbing your eye can apply pressure and friction to the surface, leading to temporary soreness or discomfort. Avoid rubbing your eyes forcefully as it can further irritate the tissues and potentially cause damage. Instead, try applying a warm compress to alleviate discomfort, and see your eye doctor if the soreness persists or worsens.