it could be eye strain or migraines,go and get both checked out
It does sound like the basic migraine,
It happens almost everytime I move my eyes in the downward out sideward direction.
def sounds like eye strain to me
I currently have an astigmatism in both eyes, andI wear corrective lens for far sightedness.
Welcome to the MedHelp forum!
You could be having a squint, astigmatism or a deviation in the axis of vision, refractive errors like near or far sightedness, low or high blood pressure of a tendency for vasovagal attack. All these can cause a headache on movement of eyes. Do consult an ophthalmologist or optometrist to begin with.
Hope this helps. Please let me know if there is any thing else and do keep me posted. Take care!