Aside from the wonky lighting, you're choosing a very challenging medium, pen and ink, and it's resulting in about two values. If you want your work to pop like I suspect you do, you need a gradation of value from black to white and all things between. Try doing some exercises to practice hatching as a way of shading to get comfortable with what you can do with your tools. Come up with eight or ten distinct values from black to white. It's basic 2-d design 101 art school exercise. I can't tell what scale this is but it doesn't look very large. It's usually easier to work larger to give you more room for detail and value study.
I've always had trouble working in color, since I was a kid. My preferred medium is black ink and plain white, I have no idea why. I'd blame the bad pen I was drawing with but a bad workman blames hisntools as they say :) I have no formal art education, just what I've learned on my own from years of drawing and doodling, simple things like crosshatching are a wonder to me.
Color is a bitch. I'm not very good at it but I don't take painting very seriously and my education in such things ended in high school. I have a BFA but I studied graphic design and sculpture. Just practicing exercises like this would help: It's an easy to learn, hard to master kind of thing. You might also like ink wash to give value. You need watercolor paper but it's a bit less technically demanding that learning how to effectively stipple. Get some brushes, india ink and a well pallette, it's basically a hubski logo that holds liquid: Put about the same amount of water in each well. Leave one clean water, then put a drop of ink in one well, two drops in the next, three drops, until you have a value scale from very light to pure black. Aqueous media isn't easy either, it bleeds and runs if you aren't patient or don't know how to control it, but it's a fairly straightforward means of creating a value scale. Don't expect to run before you can crawl so making little squares of varying shades of hatching or ink wash isn't fun but it's how you get to the level I think you want to be at.
