i get chronic migraines and one common symptom is distorted vision. if you are getting them frequently see a doctor because taking pain killers can cause rebound if theyre taken too often. rebound is when the pain killer takes the pain away temperarily but when it wares off, the migraine will come back even worse. if the migraines keep coming get an MRI just to make sure you dont have any sort of brain tumor although that is unlikely.
one thing to remember is just because a medications works for one person, does not mean it will work for you. everyone has different trigger points. some common ones are lack of sleep, poor diet, dehydration, stress, etc..