Help with acetone smell?

First sourdough starter! Lost track of the exact date it was started, but it's been less than a month, probably just about 3 weeks.

I started by following the recipe on this website:

https://www.theperfectloaf.com/7-easy-steps-making-incredible-sourdough-starter-scratch/

At about the 2 week mark I was afraid I was overfeeding it. I think I thought this because the starter had a really, really nice smell (enough that it made me want to cook with it) but I wasn't really smelling any "sourness". I also have a very cool kitchen, which I figured slows the whole fermentation process.

So anyway, there were two days where I did about 36 hours between feedings, and at the end of that an overwhelming acetone smell had developed.

I got it back on its normal feed schedule, but it's been like a week now and the acetone smell hasn't gotten much better. I thought I would be baking by now, and I'm starting to feel a bit discouraged.

Any tips or advice would be much appreciated!