How significant is it to be at the top of a Google search in less than a month? And a few more SEO questions..?

[Cat]

I have an Ebay store, and although I am just starting to learn SEO the store is already coming up in Google searches (even without using quotes) in less than a month. I know from my research this seems really quick. Am I correct? (It's not an unusal name at all, and I would share it, but after asking a variation of this question yesterday and including the name, it was already coming up third in a search with the first two being my store so I've since deleted it.)

What do I need to do to capitalize on my ranking? (As an FYI, I sell women and girl's upscale brands of gently used clothing.)

I own the domain name as well and plan on building a site so should this also help my site?

I'm researching keywords and phrases pertaining to my store, and I get the concept of implementing these organically, but just to double check, does this mean, for example, I should work in these various phrases on the home page plus my item titles and descriptions?

And I assume I should establish my categories using them too? For example, GoogleAdWords shows that "Dresses for Women" is searched for 1,000,000 times in the US per month so this tells me that would be a good category name, and I should also try to use it on my pages that feature dresses for women, correct?

Thanks in advance for any insight!
I meant to clarify that my store comes up in the top 2 spots both with and without quotes when searching the store name on Google.