"i&#039;m 17 and on 60 mg of vyvanse. i weigh about 112 lbs. i don&#039;t know if it&#039;s too high a dose, but ever since i got it increased from 50 to 60mg. i&#039;ve been feeling actually tired, which is a surprise to me because it&#039;s a stimulant. i&#039;ve also had more intense dizziness and headaches, and i had heart palpitations on the 50, but now they&#039;re more frequent, and chest pain, heart races, but i&#039;m able to focus a little better."