It can be bad if you didn't do some research and weren't prepared for those situations. Good investors knows that possibility and they fully understand the risks in markets.
They do things that can compensate loses if it happens.

When you don't fully know what are you doing it can give you detrimental effects. Unless you effortly try to change your thought and expand your knowledge you can't away from those kind of stresses.
Our mind needs a sense of security and that can only be gain through the vast experience and abundant knowledge into something.

In this link I searched show how bearish market affects us. It also gives reminders about the most known crashes is markets and signs when markets are going to crash.
https://www.investitin.com/crypto-bear-market/