PTSD symptoms usually start soon after the traumatic event, but they may not appear until months or years later. They also may come and go over many years. If the symptoms last longer than 4 weeks, cause you great distress, or interfere with your work or home life, you may have PTSD.

There are four types of symptoms of PTSD

  1. Reliving the event (also called re-experiencing symptoms)
    You may have bad memories or nightmares. You even may feel like you’re going through the event again. This is called a flashback.
  2. Avoiding situations that remind you of the event
    You  may try to avoid situations or people that trigger memories of the traumatic event. You may even avoid talking or thinking about the event.
  3. Feeling numb
    You may find it hard to express your feelings. Or, you may not be interested in activities you used to enjoy. This is another way to avoid memories.
  4. Feeling keyed up (also called hyperarousal)
    You may be jittery, or always alert and on the lookout for danger. This is known as hyperarousal.

From the National Center for PTSD, US Department of Veterans Affairs. http://www.ptsd.va.gov/public/pages/what-is-ptsd.asp