Took being 3 seconds in to see that there is some real effort put into the production and utilization of the stereo-field here. Wonderful use of panning and mixing techniques to add some real aural intrigue. There are a myriad of different instruments and voicings present throughout with some solid rests to really add emphasis to some sections. Speaking of - those glitching and bit-crushed pieces of ear-candy used to transition between sections are fantastic. They kind of creep up on the listener then envelope them and pass them off into the next part of the song.
The heartbeat partnered with some tempo modulation and even more of that glitching is genuinely super clever and a fantastic way of creating an audible example of anxiety and how it builds. The suspense that comes with that tension continuing build and never quite letting go is really great. Having the track end out on a call-back to previous sections using the same instruments and melodies from before is genius.
This felt like going on an adventure in a lot of ways. Some really great work here honestly, and all mixed and produced well. Best of luck!