Sharp pain 10 months after PRK laser eye surgery - what could be the cause?

I have sharp stabbing eye pain after 10 months from having PRK surgery. The pain is so severe that I can’t drive or even open my eyes during the painful episode and my eye doctor said it’s just dryness but I feel like it’s something else. It wakes me up in the middle of the night and it lasts up to 1 hour, it doesn’t happen everyday but once or twice a week and pain is excruciating. It also only happens in one eye and never in both at the same time.