Allergic Conjunctivitis: This condition is a common reaction to allergens such as chlorine in swimming pools, which can cause eye swelling, pain, and discomfort. The pain radiating to the ear could be referred pain due to shared nerve pathways.

Chemical Conjunctivitis: Exposure to chemicals like chlorine or other disinfectants in swimming pools can cause chemical conjunctivitis, leading to eye irritation, swelling, and pain.
Viral Conjunctivitis: Also known as pink eye, this highly contagious infection can cause eye swelling, redness, and pain, and can be spread through contaminated water.
Bacterial Conjunctivitis: Similar to viral conjunctivitis but caused by bacteria, this infection can lead to more severe symptoms, including significant discharge and vision impairment.

Orbital Cellulitis: A serious infection of the tissues surrounding the eye, which can cause severe pain, swelling, and vision loss. It requires prompt medical attention to prevent serious complications.
Endophthalmitis: A rare but potentially devastating infection within the eye that can result from trauma, including chemical burns from pool chemicals, and requires immediate medical intervention.
Temporal Arteritis: Although less common in the context provided, this condition involves inflammation of the blood vessels and can cause pain in the temples that radiates to the eyes and ears, along with other systemic symptoms.

Cavernous Sinus Thrombosis: A rare but potentially life-threatening condition that can arise from facial or sinus infections, leading to symptoms including eye pain and swelling, and radiating pain.
Dacryocystitis: An infection of the lacrimal sac, which can cause pain, swelling, and discharge in the eye area, and might radiate pain to the ear due to the involvement of facial nerves.
Herpes Zoster Ophthalmicus: Shingles affecting the eye, which can cause severe pain, swelling, and potentially lead to complications like vision loss if not treated promptly.