I have these visual migraines with an aura too.
I’ve learned to recognise my triggers (we all vary on these, but some are very common). You will learn yours too, so you can take as much preventative action as possible and act promptly as soon as an aura starts.
For me triggers are - bright lights or flickering lights (especially fluorescent) and bright sunshine. Helped by good quality sunglasses and a sunhat. I never go anywhere without sunglasses - even in winter. I’ll even put them in indoors if artificial lightings too bright.
Dehydration - I always drink a lot of water and if I have a hot drink I’ll have a glass of water too.
Being stressed or overtired. Or if I’m ill with something else.
Not eating regularly. Carry an emergency banana or some nuts for a snack. Make sure you have regular meals.
Changes in atmospheric pressure - flying is a trigger so I load up on lots of water and wear an eye mask.
Treatment for me is always taking preventative action - everyday! If the aura comes on sit down, drink water and take two paracetamol (I always carry these with me at all times). Keep eyes closed until the visual changes (holograms or kaleidoscope changes to vision) pass. Usually takes around half an hour.
Have had vocal changes twice. That does pass - scary when it happens though. I don’t always get a headache but always feel utterly drained so I do lie down for a rest if at all possible. Obviously tell your family and friends so they are aware. Sometimes it happens when I’m out - if so I try to get at least somewhere I can sit until it passes.
Go and see your GP to get it recorded that this has happened. Get your eyes tested.
Sorry you’ve had this - it’s scary at first but you’ll learn how to manage it.