Every noob on kong does one of these. The creator of the tutorial was stupid too, the snake DOES NOT go through the wall. You should die when you go off the edge.
Note to developer: Your control choice sucks. If you need the mouse to aim, and you have keys on the keyboard, USE WASD NOT ARROWS. I would use wasd to move and jump, reload with R mouse to aim and shoot, and q and e to switch weapons. There's no reason to have crap controls.