Hello dear and welcome to the medhelp forum. Your symptoms of recurrent acute headaches, unilateral in distribution are suggestive of migraines or cluster headaches. Photophobia, pressure behind the right eye, is seen with migraine headaches. Keep a close watch if you can narrow down any triggering factors in diet or environment. Keep a record of the food items, which lead to an episode. Do you get an aura or a strange feeling, like getting weird smells or sensation that you are about to have a headache? Consult a neurologist for assessment. Management involves a trial of oral painkiller along with anti emetic. There are specific anti migraine medicines to abort an attack. If the frequency of headaches were more than four a month, you would be prescribed drugs that prevent an attack. Avoiding the triggers is important. Wishing you all the best.
Sounds like a migraine. Sometimes an icepack or bag of peas or something on the back of your neck can relieve this headache, or over the counter ibuprofen (if you don't have allergies to it). If that doesn't work, go see a doctor, not an opto.