Sometimes, on my lowest days, I think about all of the things I haven't done yet. I get a rising panic in my throat and I think, "what've I accomplished so far?". It's this feeling that while I'm stuck in the mud, spinning my wheels, everyone else is shooting far ahead of me.
The problem with how we're brought up in today's world, is that we're taught there's a "perfect timeline" that your life will follow if you do everything the "right" way. The timeline is this: twelve years of schooling, about another four of higher education, career, love, a fulfilling life, and a happy retirement. That's the target. The timeline says that by 18 you should be in a good college, making good grades, and so on. For some people, the timeline works beautifully...for others not so much.
And you know what? That's okay.
I've found, and I try to remember, that you shouldn't try to measure your life to someone else's. It's okay to move through life at your own pace. Life isn't a race. As long as you're making some kind of progress, even if it's slow, you're doing alright. As long as you have a goals and you're taking steps to reach them, you're doing okay. Being frustrated because of where you are not going is normal, but it's also unproductive. You'll get where you're going when you get there.
The wonderful thing about life is that it changes, and you do too. So, if you're feeling stuck, motionless, unmotivated... remember that this is just one phase of your journey.
So, take some advice from Walt Disney, and keep moving forward.