Just a couple of questions to help me better evaluate your case:
Was there a headache associated with the episode either during or after the episode?
Do you suffer from any medical conditions?
Are you taking any medications?
Your description is consistent with an ocular migrane. Ocular migranes can occur suddenly with visual distortions like the ones you experienced. They can be associated with a headache but not in always.
Episodes of hypoglycemia (low blood sugar) can also cause visual symptoms but usually you would feel lightheaded and sweaty, which you did not experience.
There is an entity by the name of TIA (transient ischemic attack) in which the circulation to the eye is compromised by a cholesterol particle that is dislodged from the carotid arteries and travels to the eye to temporarilly occlude a blood vessel. This, however, usually occurs only in one eye and lasts for approximately 5 to 10 minutes. Given your history of good health and the occurence to both eyes simultaneously this condition is unlikely.
Ocular migranes do not have any long term effects although they can significantly interefere with our lives when they occur frequently. If they become associated with a headache then a visit to a neurologist may be indicated to obtain medication that can be administered at the onset of symptoms to then avoid the headache associated with the migrane attack.
I hope this is helpful and feel free to ask any other questions you may have regarding this episode....
I am glad I could help...