Ok, I quit at the long jump bit. I got past it once, and then died straight away, so I gave up.
Now the game, especially for your first, is pretty good.
HOW TO IMPROVE
1. The snek movement needs a little work. It's a little fast. (No sliding is good though)
2. The camera should be zoomed out more and not move so quickly.
3. Checkpoints. If you want people to try and get through without dying, use badges. That way, it can be completed easier, but no deaths is more of a challenge.
TWEAKS
1. Make the graphics consistent
2. Make the reload happen much quicker after death
3. General game rule: bad objects should have slightly smaller hit boxes and good items should have slightly larger ones.