No, guess no one is the only one.
When I was diagnosed with PTSD I blew it off, then another psychiatrist gave me the same diagnosis and ....
You may have already read information on c-ptsd and this may be why you don't recall "the trauma"---it may be an accumulation of insults over a long period of time and may begin before you can talk or understand what is going on. I also found, over time, that I normalized events that were obviously traumatic---and wondered why others took them so seriously. The emotions came long before the ability to identify any "traumas".