I liked the game a lot, you really nailed the feeling of an obscure NES title forgotten by time! Graphics and especially the music are very good.
There were unfortunately a couple of things that were driving me insane. The controls were not precise enough for the gameplay, I especially did not like the sections where you had to swing with the tongue, letting go and landing somewhere or swing again on a different point. I would have liked it a lot more if you just held the tongue button and let go of it to release, instead of pushing it again, that felt really unintuitive. I also think swinging pendulums in a speed oriented game fit the theme well, but don't make for the best level design. Waiting for the cycles to hit the right spot over and over again is really tedious if you need to go fast. The most irritating thing for me was the final section being accessible from the start but in it's blue state. It gave me the impression that I could take this challenge once I decided that I collected enough clocks and a better player could take this challenge earlier as a way to adjust the difficulty yourself. But that was not the case. I was able to turn up the platforms that you have to move up by hitting them with your tongue, but painstakingly slow. I thought at this point that the room was just a tedious test of patience, but I could not make it in time. So I decided to explore more to find more clocks and when I found all of them, the state of the section changed and it was suddenly doable. I would recommend not making the section available from the start or at least make sure that the platforms don't move at all, so the player knows without a doubt "I'm not supposed to do this room right know".
These criticisms are mostly level design and controls, I hope it helps. I had a good time with the game nonetheless and would love to see how you improve making games in the future!