I have to say, you have a very adorable art style. (Not adorable like watching a little kid try to make art, but adorable in the sense that it's well made and cute. If that makes sense. :P)
I love it. :)
Though, I am a sucker for cartoon style art, so your paint.net stuff is what I adore the most. xD
As for your sprites, you're doing an amazing job with them. I think if you keep practicing, though, you'll get even better results. My only complaints there are that recolors are very easy to do and take about like a few minutes at most (They are very fun to do, though! I did a lot of spriting back in the day, and I love recoloring.) so they aren't as impressive to show off, but you did get some nice color schemes. And for the cave, the ground is perfect, but the walls could use a little more detail. It just doesn't seem like a cave wall. If you give it a bit more of a stone texture, I think it'll look a lot better. :)
As for your pencil art, I can't offer advice there because I'm not too good with pencil art, but I honestly think you did an amazing job with it. I have no complaints there.
Overall, I really like your art and see a lot of potential in you. Keep doing what you're doing! To be honest, when I saw your paint.net images, you already hooked me as a fan. xD
