Thank you for sharing your concern. Honestly I don't know as I have any answers for you with regard to this. But I noticed no one had replied to your post. So I thought I would.

From my perspective, there's no good answer to the question you pose. If you "just let things keep progressing naturally" you run the risk that this lady may decide you're not serious. But if you jump in with both feet & try to make your relationship official, it's possible you could find out she's not ready for that or, as you mentioned in your post, you could scare yourself & wreak your own chances. There's simply no way to know for sure.

My personal inclination would be to simply allow things to progress naturally & see where they go. But that's just me. It doesn't mean it's the best approach. (Perhaps other PC members will yet have some suggestions they can offer.) Maybe the important thing to keep in mind here is simply that good communication is the bedrock of any successful relationship. So here are links to some articles, from PC's archives, on that subject:

5 Things Not to Do in Your New Relationship

How Do You Know that You're with the Right Person?

9 Steps to Better Communication Today

Communication Pitfalls & Pointers for Couples; Psych Central

Nourishing the Different Types of Intimacy in Your Relationship

https://psychcentral.com/blog/10-que...-deeper-level/