Hank here from Shopify.
It is very important to offer your customers a seamless way of shopping, and having your store in their chosen currency is a very good move for you to consider.
Your store currency can be changed within the admin (Settings > General), but as you have correctly mentioned, once you make your first order (congratulations by the way), you need to reach out to Shopify.
That is where I come in!
As this is account specific, I will just need to verify your account. I will send you an email to the email address attached to this forum's account and confirm some security questions about your store.
Once you reply to that email, I will look into this further for you.
All the best,