Twitching becoming worst, help?

For about idunno how long, but i knows it longer than 5 months.. I've been twitching in my neck, arms, shoulders, behind my shoulders, and legs. I've talked to my parents about it and they think i'm fine, but i'm not. I'm 15, 4'11 and 120 pounds. I workout but i do very calmly and have a normal diet, i am under no stress or anixtey. No problems in my lie atm, and i dont have ALS, (amyotrophic lateral sclerosis). Is there any dieaseses that might relate to this?