Actually venting problems with the person may help them understand that you dont like or wont tolerate his or her behavior and can help understand not to do it in the future with other peers. It's never good to be shy and scared please speak up.
It is not healthy to respond to conflict in avoidance. When a problem first occurs when our emotions go up, our intelligence tends to go down, so it is best to wait a while if you feel you are not coming from a neutral place. But conflicts should always be effectively communicated and addressed to sustain healthy relationships.
