Can you get norepinephrine levels checked? if so how?

Yes: Generally checked in blood &/or urine; byproducts of nor-epi are generally checked & 24 hour test may be needed. The levels in blood and urine don't necessary reflect levels in the brain. Checking levels in the brain would call for a spinal tap and not performed in routine practice. Unless looking to diagnose pheochromocytoma, no other medical reasons are indicated for checking nor-epi levels.

Catecholemines: Norepinephrine is a hormone produced in the body. There are specific blood tests which can measure these levels in your body. Norepinephrine is related to your bodies "fight or flight" response. It can also related to your mood and possibly depression.