It depends on what your income from those two weeks was. It doesn't matter that you only received one 1099-K. You can enter sales as cash received.
This is what New York states
New York State nonresidents
You must file Form IT-203 if you meet any of the following conditions:
You have income from a NewYork source (see below and page 😎 and your New York AGI (Federal amount column) is more than your New York State standard deduction (see screenshot).
Your income would qualify as any income you received related to a business, trade, profession, or occupation previously carried on in this state, whether or not as an employee.
The complete instructions on page 7:
https://www.tax.ny.gov/pdf/current_forms/it/it203i.pdf
If you have other questions about this, ask in the comment section below.
I'm afraid this didn't really answer my question. I wouldn't say that the income was from a New York source, as I was making sales from people from all over (i.e. I wasn't "employed" by any NY company). I am an artist and this was a small temporary popup event where I sold my artwork. I was there for two weeks and it was probably less than 10% of my total income from all sources.
And it was not income related to business previously carried on in the state, as it was my first time selling there.
So it does not seem like I need to file, but I'm not 100% sure?