Nice job, this game is really interesting! I like the music and the vibe, and the mechanic here is both interesting and well connected to the theme! Great job!
Couple things. To start with, there were a few glitches. In one of the levels, you could walk off the edge to the memory thingy with the non-inner self John. If you did so, he would be frozen, but he would be able to go into his walking animations, and if you held jump, he'd just... flip out, haha. If you are close enough to the edge of a platform, you can turn that character into the falling sprite without actually falling. Nothing gamebreaking, but just thought it should be mentioned.
One thing that kept happening was with the seeds of doubt/spikey plants of doom. They seem almost TOO sensitive. There's no buffer around it - it often felt like I would literally touch it with one pixel, just one, and have the whole level reset because of it. It got annoying when I couldn't even tell that I touched it. Nothing too major, but it was definitely something that took away from the experience for me.
Overall, this is some good work! Good job!