Hey Jack,
Welcome to the forum!
I like your lil dude, good pose and a nice amount of character from such few pixels is a good start.
Your image does have a few problems though, hopefully highlighted in my edit:
![](https://33.media.tumblr.com/49a0ae34b7b34dcd6985da40d125208a/tumblr_nfuu90l6em1u3fa1zo1_100.png)
Might of taken the design in a "jockier" a direction then your after, but I hope you get where I am coming from.
I tried for a blockier approach, it's good to get your base shapes down with some solid contrasting colours. At this size (and I do recommend you post x2, monitors are a bit higher res then they used to be ;p) readability is the most important thing, you can get a bit fancier with your shading sure, but only after you have readability down. I also eliminated all the outlines for this reason, you don't have enough pixels to work with to really make them super viable.