Adderall XR - Am I taking a dangerous dose?

Hi, Donya!
That's a pretty high dose unless it's been prescribed for you off-label by a licensed professional.
"Maximum Dose: Only in rare cases will it be necessary to exceed 40 mg per day."
One of the real dangers is addiction in which case you'd need to do an extended taper under the supervision of your doctor to avoid withdrawal symptoms. There are also the short- and long-term side effects of taking amphetamines in high doses.
You might seriously consider getting professional advice.
Best regards,
Wildcat