Children are at a greater risk for not coping because they are still developing their personalities. There are a lot of people who cope that way, but many don't. To understand our reactions, we have to understand the symptoms. PTSD is reliving the event, such as seeing it played over in your head or having nightmares about it. Withdrawal is not doing the things you normally like to do, including not spending time with family or friends.
Excessive behavior involves irritability and angry outbursts.
These reactions try to prevent surprise, such as sitting with your back to a wall so no one can sneak up on you. Within a couple of days, however, if you're having trouble doing normal work, I would suggest talking to a professional. Denial is a well-known method of coping with a traumatic event and allows the person to feel comfortable in certain situations, though it may not be the total answer. But when coping involves substance abuse or dependence, attention to the matter is required. Abuse is misuse of substances for longer than a month that puts people in a dangerous situation, such as drunk driving.