PTSD requires a proper diagnosis so it seems silly to need to create a page telling people what it isn't. PTSD however, has become a "trendy" disorder. I know seems stupid, why would anyone want a disorder. These people who claim to have PTSD don't really want the issues that come with PTSD, they want the sympathy and attention that they think PTSD will get them. This in itself maybe proof of some type of personality disorder but not PTSD.
PTSD is a long term disorder. So you can't know a week or even a month after a trauma if you will develop PTSD. So don't come to a PTSD group three days after a trauma and claim to have PTSD. You may develop PTSD however, if you are seeking attention that soon after, it is unlikely, as one of the primary symptoms is avoidance.
PTSD doesn't come from single small trauma events. By that I mean single events like rejection in a relationship, a pets death, or a simple injury do not manifest into PTSD, they may follow a similar short term path but, as I said before PTSD is a long term disorder.
CPTSD may come from many smaller traumas that have a cumulative effect. However, even in CPTSD the trauma is often large enough to cause PTSD after a single exposure.
So what are the type of trauma that can cause PTSD? Well it is generally accepted, that trauma that engages fight or flight is required to cause PTSD. So this means life or death type situations, witnessing a violent death, being a victim of rape or witnessing a rape, major assault or witnessing a major assault, being in combat situations, domestic violence physical or mental, child abuse, or any type of event where your personal space has been violated in a violent way.
So what trauma doesn't cause PTSD? Well, pretty much everything else. You don't develop PTSD from putting your dog to sleep, from having a someone breakup with you, being in a fender bender, or as insane as it sounds being banned from a Social Network(yes I have had people tell me that they have PTSD from that).
All of that being said, that doesn't mean that a person with multiple small traumas in a short period of time and existing mental issues may not develop symptoms of PTSD or even CPTSD itself. You have to remember though that PTSD is a complex mental disorder that has symptoms of a wide array of other disorders and a long list of comorbid condition both mental and physical. It often takes months to years after a person seeks treatments to be properly diagnosed with PTSD.
So what it boils down to, is if you immediately suspect PTSD after a trauma, it is unlikely and you are less likely to develop PTSD down the road, you are dealing with your trauma. PTSD is often manifest after rejecting and refusing to deal with the trauma. PTSD at its heart is a case of your stress responses either being continually engaged or repeatedly engage via flashbacks, night terrors, nightmares, memories and reliving experiences.