Make sure you're using references for things like this. Here's a quick one I found:
Since I assume that while you're trying to stick with a cartoony style, you're also trying to base it on reality, some errors some into the spotlight after looking at the reference:
- The eyes are basically on the side of the face, whereas your are near the front.
- The Psuedo-chin (since I'm assuming it's not called a "chin" on a snake...) is pretty pointed and follows the tapered-bullet design of the head, whereas yours is pretty broad and flat.
- Nostrils. Huge ones. Most snakes have them.
