Yes, I'm sure it was a ton of work, nice job! My first bump was on the cat boss: I was in the process of figuring out its patterns and was making progress after a few deaths, but then I happened to shoot out the leaf it was perched on (on the far right-hand side) from underneath it, and this caused it to (as I recall) hop down and then up onto another perch on the upper left of the screen. So I climbed up the unfurling leaves on the left hand side, but realized then that it had just stopped fighting. I dashed through the wall to stand right next to it, and it still just sat there, motionless, as I hit X a bunch of times and defeated it. I was a little bummed to not fight it at full strength :).
The other bump I had was that when I first finished the game, I heard the heartbeat (if I recall correctly?) and the screen dimmed to black, but that was it, it just stayed black. I exited full screen mode and I think then it was solid gray, but it never "came back." I exited the page and restarted the game, and this time collected 9 hearts and then finished (thinking perhaps it was a lesser ending for that reason?), and this time I got the credits. But I suspect the first experience with the end was unintentional.
I hope that's helpful, very fun game, thanks for making it!