I feel like I'm wasting my time away.?

I am 15 and have felt the same way. I have an 8 year old brother. First of all stop crying, its ok and its not too late. Offer your brother to play with him in any sport or actvity he likes. Make an effort and be approachable.Casually talk to your parents and be more friendly(conversation will come more easily). It won't take long for things to fall back into place. No worries