Here's the review I promised!
The (extremely) fast pace and sudden turns certainly take some time to get used to, but it can work if they work towards a coherent goal. If there is one thing I could give as advice, it would be to identify that goal. Stories are (in my opinion/experience) written to evoke a certain feeling in the reader and/or send a certain message.
This is a little hard for me to find in your case, but it seems to be that you can experience the strangest things and still move on with your life afterwards. This doesn't quite come across because both the opening and the ending don't seem to be clearly built around that idea. I understand that you are more of a discovery writer and like to see where the story takes you, and that's a completely valid approach, but you should still revise certain parts once you're done.
Very concretely, you could structure it in the following way:
1. Describe how ordinary of a day this is and how ordinary the main character is. They appreciate the small things in life, like the birds and the quiet woods. Suddenly, they get the opportunity to explore this building and so they decide to, just once, be a little adventurous.
2. Inside, everything happens the way it did now. Perhaps with some more detail, but I understand that's beyond the scope here.
3. Once they are back outside, the main character again learns to appreciate the more quiet aspects of life and learns to be grateful for what they have.
Overall, I can see the effort and think your free-flowing writing style is interesting. The important thing to learn, assuming you want to keep writing and this wasn't a one time thing, is to later look at what you have and think about how various aspects of your story can contribute to a larger whole.
I understand this review is probably a bit overkill for the kind of project you were trying to make, but I hope it can help you develop your craft. Just keep writing! I can already see you have a unique style, and now it's just a matter of practice to make it work for you!