Follow the advise you were given and see an Eye MD ophthalmolgist. The cause can be infection, allergy, swelling of the conjunctiva (chemosis) or cyst, tumor, etc.
Need an inperson exam by a Eye physician.
JCH MD
It is almost like a blister under my fathers eye. He didn't hit it or rub it. All the sudden it just appeared. This has happened before but the doctor told him to come back if it ever happened again. Anyone got any advice on what it might be.
Most common cause "chalazion" search that term. See an Eye MD find one at www.aao.org
JCH MD