My name is Lilith, I'm on the Social Care team at Shopify.
I'm glad that you were able to clear that up on your side. For any others that drop by this post here and for any future instances that you may experience this, I have a couple of things you can check on to make sure that you know what is happening with your store.
If you're ever encountered with an error message like that it's a good idea to double-check our status page just in case there are any current situations that the development team is working on. Normally the page will show when it started and any other details to help merchants experiencing the issue. Our developers work rather quickly to resolve any situations and will update the status page immediately upon pushing any fixes.
Sometimes a quick cache clear can help with any browsers that had any trouble receiving the fix. However, be sure to check the status page before doing this just in case there are different recommendations.
If the error you're experiencing isn't on the status page, we urge you to contact our live support team as soon as you can. In those cases when the status page doesn't reflect a specific error you're seeing, it could be that it's newly unreported by others or a localized situation. By contacting the live support team versus forums you'll get to speak to an advisor right away and they'd be able to authenticate you to check your account to determine what your next steps need to be for resolving your situation.
Now that things are all back up and running for you, I hope that sales are will go well! Have you launched your store and started marketing your brand yet?
Let me know how you do with the information above! I'm happy to answer any questions you think of as you work on your business.