Yeah, I'd say you can easily improve. I just started with Famitracker 2 or 3 months ago and I've gotten pretty decent at it. My musical knowledge if limited, very limited yet you can see how I can still pump out some decent covers (see my most recent cover from Megaman ZXA for an example of mine). Basically, if it sounds good, it is good. I may not have a good grasp on music as a whole, but I can definately say I have a good ear for music. I'm not gonna lie, I have a hard time hearing notes too, but I'm not gonna hide behind that excuse. Instead, I'll use that as my drive of motivation and use it, making me feel the need to improve rather than drop to my knees in despair. Start by improvising. If you can't hear it clearly, mix it up a bit. Take what the song gives you and make it your own and use it as you please.