GAD would seem to be a good fit, if you understand GAD.
You have described at length your generalised panic, anxiety and worry (about the risks of doing anything from brushing your teeth to trying pushups,) and excessive stress. Dissociative states? Can also be a feature of GAD. Unlike Ptsd (or cptsd, which is not an official diagnosis), there is no requirement for criteria A trauma or re-experiencing symptoms, which are central to ptsd, and which you don’t appear to have.
GAD has a lot of overlap with ptsd. Which would explain a lot here for you. Right up until the DSM 5 was released, ptsd was considered to be a form of anxiety disorder.
GAD was a diagnosis suggested by someone qualified to offer a diagnosis. Cptsd is, like BPD, just something you feel you relate to. That’s really not how diagnosis works. Your self-diagnosis of bpd is one example of why self-diagnosis is such a bad idea.
There are plenty of examples here on this forum of people who have ptsd from preverbal trauma, and plenty with ptsd (or cptsd) from trauma that was recalled only after delay. But I think you’ll find that for most (all?) of them? Ptsd was not offered as a diagnosis until it became clear “this is ptsd, all the criteria are met”.
What you have done with your T, is decide “I relate to cptsd, so I must have unrecalled trauma.”
Any therapist who gives a ptsd diagnosis in the absence of any recalled trauma, is encouraging you to believe that there is preverbal or unrecalled trauma by doing so. Quite apart from ignoring a diagnosis offered by someone qualified to diagnose? He is encouraging you to believe that you have criteria A, currently unrecalled, trauma.
This is in strong contrast to best practice in trauma-focused therapy, where it is now well documented that it is incredibly important for a T (or anyone) to stay completely neutral on the question of whether there may be unrecalled trauma, so that the brain can recover anything that needs recovering at its own pace.
Where therapy encourages a belief that there must be unrecalled trauma, we know that the brain will quite obliging make it up to fill the gaps in accordance with what is being suggested.
If there is unrecalled criteria A trauma? It may be that you have ptsd. If there isn’t? Your therapist, in extrapolating what may have happened to you in infancy, is doing far more harm than good.
GAD actually seems to go a long way in explaining your distress, symptoms and experience. Adopting a cPTSD diagnosis (much like adopting a bpd diagnosis), because you like it more than a GAD diagnosis? Isn’t going to help you.