I just played this and it was really something! For your first game (public at any rate), you did a great job, especially with the time constraints in place. 30 days is not a lot of time!
Anyways, some spoilers ahead for people who wish to avoid them...
I really enjoyed the custom art work. Upon first glance it seems fairly simplistic, but I sort of feel like that somehow makes the game a bit better and more relatable since having super detailed characters would not really allow the player to project themselves onto the main character of the story. The sprite graphics and colors were interesting and the mild hues seem to play into the overall theme of the game. The music didn't stand out, but I feel like it wasn't supposed to - it blended in well with the scene in which it was present and augmented the atmosphere in a subtle way.
I did not get a chance to find the girl's friendship bracelet unfortunately, as I ended up finding the storeroom first before really exploring. I feel like there is the potential to accidentally halt progress in the game if you get the chair stuck in the corner since it doesn't reset its position if you leave and come back - so if someone messed up, it is basically game over. The only real issues I had with the gameplay itself is that I had no idea how to open my inventory to find my keys. I hit the escape key to try and bring up the menu to no avail, and then I ran around and discovered a passability error (I assume it is anyway) that let me run around in the darkness near the street lamps and it was difficult to find my way back lol (perhaps an unintentional metaphor there...), eventually I just pressed random buttons on my keyboard until I found the right one. A little heads up about how to open that menu would have been cool, though I suppose not knowing how to open the menu could also greatly play into the overall theme of the game - or perhaps I am reading too much into it! :)
On a more personal note, when I was younger I had anxiety, especially about meeting strangers or going to places I was unfamiliar with. As I grew older that went away over time and in spite of being overall an introvert, I have no problems with meeting new people. I wish it happened as fast as it did for Yuu taking his first step with meeting his mother's new boyfriend, as it is a journey that takes far more time, but I understand that the game needed to be wrapped up. You captured the general essence of anxiety induced by social situations fairly well I thought (if maybe a bit more dramatic than I experienced). It feels like this game is a rather personal story for you, so thank you for sharing it. These feelings of anxiety do get better with time until they are nothing more than a bad memory.
Good job and keep up the great work!