a bundle of nerves

US /ə ˈbʌndl əv nɜrvz/
UK /ə ˈbʌndl əv nɜrvz/
"a bundle of nerves" picture
1.

a person who is extremely nervous or anxious

:
Before her big presentation, she was a bundle of nerves.
Waiting for the exam results, he was a bundle of nerves.