This is a good job for a first 3D game! Well done!
I agree with previous comments that the jumping was difficult, which in turn probably made some levels harder than they should've been. Level 2 comes to mind where I wasn't able to consistently land jumps off the moving platforms because it was hard to see what point I was jumping off. If you plan to refine this, I would love to see the controls/difficulty balance better!
In addition, I can't help but feel the red platforms are somewhat unnecessary. To go back to the second level, if you jump on the moving red platforms then you're stuck on them until you decide to walk off and die. If the player is going to end up in the lava to begin with, are they needed at all? I feel these platforms also really ramped up the difficulty in unnecessary ways.
Regardless I feel this has potential to be a really fun platformer with a little more balance and refinement! Once again well done :)