The mistake is so cute haha!
Basically the first thing I'd do is try making the lines longer (even though it's just a sketch) instead of lifting the pen and breaking them, if you know what you mean. It takes some practice but you'll get it! Other than that, you should just continue drawing and developing your style. Don't forget that even if you want to draw manga or any other style you should still work on anatomy because it's really important.
You're on the right track!
I just would say the hair looks a little...odd. Mostly girl (the guys hair looks pretty good, if not a little too big for the head), it looks kinda like noodles or something.
Try either using thinner and more strands, or one mass, with strands coming out. (If that even makes sense >.<)
Other than that, I'd say just keep working at it! Draw as much as you can and keep it up!