Any time you get the auras, it's called an ocular migraine, assuming you've not had a recent head injury, etc. You don't have to get the headache for it to be a migraine.
Do you get any other symptoms? There's also something called a silent migraine, where you get the other symptoms of a migraine - nausea, inability to sleep, sensitivity to light and sound, etc. - but don't have the actual headache. I get these, and instead of the actual headache, I get the chills so bad my teeth chatter.
Have you recently changed anything that might be causing you to trigger more migraines? Moved? Started eating new foods or be exposed to allergens or chemicals? Started working with someone who wears perfume or cologne? Is it happening more at home or work? Fluorescent lighting?
It's good you have the appointment to rule anything else out, but it's probably not anything serious, if that helps while you wait. :)