Brief Answer:
Read below.

Detailed Answer:
I read your question carefully and I understand your concern.

While the intensity of the trauma may have not been of the highest impact, the fact that you have had more than one traumatic event in the same day has contributed to the extent of damage and the long recovery. That is because early after one first event the nerve cells are more fragile and prone to damage in the case of a second event occurring so early.
For that reason you were and indeed are having some long term consequences from those injuries. It is not uncommon for symptoms such as headache, fatigue, sleep issues, slowed thinking, memory issues etc to persist for months, in some cases even years.

Coming to the mechanisms of that, you have obviously doing some reading yourself judging from the mechanisms you mention. I can say that often it is a combination and not one simple mechanism. Furthermore as much as these physical factors there are also psychological factors contributing partially and at times it is hard to assess to which percentage. I would say that after 7 months the initial metabolic changes have usually returned to norm so I wouldn’t say they do contribute. Also I wouldn’t think about protein tau depositions in your case, apart from that being still a matter of study it is more a question of repeated trauma over a long time I do not think that to be your case.

I would say that the most probable mechanisms are neuronal cell loss and changes in neurotransmitter levels. Neuronal cell loss at a microscopic level is possible even in the presence of normal imaging and months may be needed for new connections to develop between the remaining nerve cells to compensate for the loss of function of the lost ones. Furthermore that could lead to neurotransmitter changes to cholinergic, glutamatergic and adrenergic pathways.
Of course these are only hypothesis as unfortunately there are no lab tests to confirm these theories. Moreover as I said before psychological factors and anxiety often partially contribute.

As to what you can do….I would say not much, just have to give it its time, there is not a drug or a particular regimen to have shown benefit, only thing is to resume activity gradually over the first months in order not to overload your recovering brain and to allow it its necessary rest. So I would say the opinions of the doctors you have consulted till now, do not differ that much between them, at times doctors use different wording to explain similar things. I would disagree a little only with the last one who used the age argument, at only 41 I wouldn’t agree much with that.

Let me know if I can further assist you.

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