Great start! 

Here's my feedback: 

Not being able to change your direction mid-jump definitely makes it more challenging. If you can figure that out, I feel like it will improve it and add more depth to future levels.

Music is a little repetitive in the first level (I enjoyed the music more in Level 2!)

I made my first game at age 11 too and 20+ years later I'm still improving!

Excited to see what you come up with next!