I am not certain that I know what is occurring in your life. It would be wise to set up an appointment for psychological testing and a neurological evaluation. You said that you have seen both a psychologist and a psychiatrist. You should ask them to conduct psychological testing or ask them to refer you to a neurologist. Testing may help you rule out a neurological condition.
You remarked that you have a “hyper-flight and gap” or no “fight response at all.” I am not sure that I fully understand what these remarks mean. You have described two situations in which you feel that there is a delay or gap occurring in your response: one in which you think that you have made the best decision possible only later to realize that you have made a glaring error and secondly, you “freeze” when there is a problem that you feel you should be able to solve or stand up for yourself but you don’t and you feel like fleeing the situation.
With regard to the first instance of this problem, you said that in these occurrences you feel as though you have made the best decision possible and later learn that you did not. You did not give a specific instance in which this occurred. I know people who have had this situation occur when they write a paper, for instance. They will complete their paper, edit it four or five times (sometimes more) and later find out after it is returned to them by the teacher that they left glaring grammatical errors. They say that they “should have been able to see these glaring errors” because after all they had read it thoroughly many times. It is not uncommon for this to occur because at some point, no matter how many times the paper is read and re-read by the author, errors can still be missed. That’s why editors are needed. People cannot always see their mistakes, no matter how glaring they may be and no matter how many times the document is re-reviewed. These mistakes by writers can occur not because something is wrong with them physically or biologically. Yes, perhaps the writer could have searched for a more effective editing method but when an individual gets too “close” to a piece that they have written it is possible to become “blind” to it. This is a fairly common problem among writers.
I am not sure if the example I wrote about above is analogous to the types of issues or experiences you are having but without more information, I can only speculate as to what you meant.
With regard to “freezing” when the time comes for you to stand up for yourself or be assertive, this is not an uncommon occurrence with individuals who have an anxiety disorder (you said that you were diagnosed with a generalized anxiety disorder). Part of an anxiety disorder is to feel uncomfortable in social situations, especially under perceived pressure and in difficult situations. People with anxiety disorders can often recount many stories in which they wished they could have spoken up for themselves and they did not, even though they had something they very much wanted to say. These types of occurrences are extremely common with anxiety disorders.
You also said that you have a genetic deformity on your hand. This deformity may make you feel self-conscious. If this is the case, it is possible that the self-consciousness that you feel associated with the deformity hinders your ability to be more assertive.
Part of what you might be experiencing may be “normal” (as part of an anxiety disorder) and you have misunderstood your situation and labeled your behavior as abnormal. I do not know if there is anything wrong with your “brain,” as you have indicated. It may be that you are still in the process of learning how to overcome your anxiety disorder, and possibly other issues.
You still should consider being evaluated neurologically to rule out any brain disorders or abnormalities but also realize that there may be nothing physically or biologically wrong with you. It could be that you are very early in your treatment recovery and there is still work that needs done. Lastly, if you feel that your psychologist or psychiatrist is not treating you effectively then perhaps it is time for a new set of mental health professionals. Thanks for writing and good luck.