Thanks for the feedback! I'm glad the breathing mechanics added to the atmosphere, I did feel like it might be a bit frustrating to have to stop and breathe every now and then so that's good to hear.
I noticed the window size too, I wasn't sure how to set up the window size properly when I uploaded the project, so it's definitely something to fix in the next jam.
I definitely agree that movement is a bit too quick – the idea was to have the player's movement speed change with the heart rate (the lower BPM = slower movement, higher BPM = faster movement) to help give the player the same sense of anxiety and panic the character would be feeling, but I think this definitely could have been clearer.
Thanks for checking it out :)