Hey, not bad! Your line and coloring work look pretty steady. I just have a few recommendations for ways to improve your art going forward.
I’d recommend you pay careful attention to the angle you take the picture of your artwork from. Try to keep your phone directly above the page and as parallel to it as you can. That way, perspective won’t get skewed and you hopefully won’t get slightly different angles for different frames in a gif like this one. I’d also recommend looking at reference images for this kind of pose, to get a better understanding of what the arms and other parts should look like. Same for the gun. You also technically drew his hand in the wrong direction, but as far as I know that could be part of the design.
Regardless of all that, the idea to make a gif using traditional art on paper shows you’ve got some creativity - don’t lose it, and keep up with what you’re doing! You’re going to make some cool stuff in the future!