overreaction
n. C / U B2 Upper Intermediate US //ˈoʊvɝɹiˌækʃən// UK //ˌəʊvəɹɪˈækʃən// over·re·ac·tion
n. a response that is much stronger or more extreme than the situation actually deserves. You use this when someone gets too angry or worried about something small.
n. a response that is disproportionately intense or excessive relative to the stimulus or event that triggered it. Often implies a lack of emotional control or an irrational assessment of risk.
His shouting at the waiter was a total overreaction.
The manager's decision to fire the employee over a minor mistake was seen as an overreaction by the board.
While the initial security breach was concerning, the subsequent lockdown of the entire campus was widely criticized as an overreaction that unnecessarily disrupted the academic calendar.
From over- + reaction.