[Blood-Pigggy]

I have these same sorts of feelings, but at a young age they're diagnosed as some disorder as something. I'm practically racking those up.
I have the constant need to be places that I haven't been before, my jogs regularly take me so far that it takes me around two hours running at a good speed to get back home.
That's a good thing, start JOGGING instead of walking, if you feel no sense of accomplishment from your walks, then push yourself, exercise to your limit. At first it can be difficult, but at some point you'll ignore the ache, and when you get home after going farther than you did before, you'll feel like you did something. There's a part of our mind that associates our ability to physically outlast our pain so that we can become stronger mentally as well, because we realize that we have the ability to better ourselves, even if we don't feel like we're making progress.

It sounds like generic highschool coach bullshit I know, but it's nothing like that. It's all about the feeling that you've beaten an older you, even if that older you is just a few days before.
Then read, read, read. Fill your head with things you don't need, think about things you've never thought about. Remember thinking about the possibility of oblivion in death and the strange feeling you had afterward in your head? Try to think about things that you'd never imagine before because it'll give you new perspective. Think when you're in a field on a jog, in a nearby park, or wherever else.
I understand that you'd think that it would only make things worse thinking about your problems, but if you let them fill you up for a bit you'll get over it. Just outlast a couple of hours of misery, instead of letting it drip in bit by bit everyday, it works hand in hand with the philosophy of making yourself stronger, just work through it and the feeling will dissipate.
But NEVER delude yourself, don't ignore problems. Try to find something that you can accomplish even further. Try learning to play different instruments, sports or whatever. Watch new genres of movies, listen to new music, on your jogs you can listen to a bit of opera for a boost. And while you're doing that think about how to fix things. As human beings we tend to think that there are only a couple of alternative solutions for a single problem, but arbitrary math problems aren't constant with things in life.

IN SUMMARY DO EVERYTHING YOU THINK YOU POSSIBLY CAN. There is no dullness in your life, there's only a sickened will that won't push you to do new things. In the last year I've forced myself to start wrestling for school, do intense physical work-outs, write fiction, get into surrealism films, abstain from useless relationships and pointless flings, and find a way to better my grades in school while at the same time ignoring the useless wastes of time that the public school system attempts to suck me up with (fucking honor society can kiss my ass).
There's only one bad point to this, you'll start thinking you're better than everyone else because you've done so MUCH yourself.
If you think there's an empty spot in your life, it's because you haven't done enough to enjoy yourself.

I can't really relate to an extreme level since I'm still a teenager and there's much I can do to influence my path in life, but I do have tendencies to follow whatever impulses I have, it's another one of those *rolls eyes* disorders some doctor thought would explain everything that makes me different.
But despite all that, despite all that generic asshole bullshit that people spew about life not being all fun and games, life CAN still be fun and games if you just let yourself be more impulsive and enjoy these things.

Society can suck a ****, they tell you to be reserved, mature, and to control your impulses, but all that does is making a bunch of crowing jackanappers who're always stuck up their ass all day. Be impulsive.