While hiking in the mountains in alaska, pete encountered a giant grizzly bear. he immediately felt his heart rate increase, his breathing become rapid, and sweat drip down his back. these events were most likely due to effects of the neurotransmitter called

Adrenaline

Explanation:

Adrenaline, also called norepinephrine, is a hormone produced mainly by the adrenal glands (medulla). Its main goal is to prepare the body to “fight or flight” response, it means that under stressful situations (in this case, fear), it triggers heart rate increase, airway expansion (to benefit gas exchange), blood pressure increase, mydriasis, etc.

Adrenaline release is stimulated by the sympathetic nervous system.

just be there for her.

explanation:

not necessarily literally but figuratively. also don't say things like "i understand how you feel", because even though you are trying to , you clearly don't understand how she feels (i'm gonna go out on a limb here and assume you've never had a heart attack). also just let her rest. that is one of the best things for you to do.