Brief Answer:
Anxiety to be considered.

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

I am not sure that the MRI you are having is going to be of any benefit, since these are the same symptoms you had in the past with a normal MRI this one is probably going to com back normal as well. Furthermore those widespread symptoms do not correspond to a specific brain or spinal cord area. MS might be considered as it may affect multiple areas, but the first MRI would detect it and also there would be other symptoms not the same ones over and over again.

If there is a damage of the nervous system it would be more likely in the peripheral nervous system, if I were to repeat an exam it would be EMG/ENG. In addition there are forms of peripheral nerve damage, like smal fiber neuropathy where EMG/ENG studies may not detect any damage, only nerve biopsy can. So that would be the only neurological condition I would consider to investigate.

However I would retain as much more likely the possibility of the symptoms being simply due to anxiety. Anxiety may commonly manifest with such abnormal sensations and the relationship with the withdrawal from Valium, an antianxiety medication, would be in favor of that. I believe that there is an underlying anxiety disorder with periods of exacerbation like the present symptoms. Judging from your age the appearance of the symptoms corresponds to the period of menopause which with its hormonal fluctuations may contribute as well.
If it is a chronic issue I would suggest antianxiety medication, not benzodiazepines which create dependence and tolerance, but antidepressants.

I remain at your disposal for other questions.

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Brief Answer:
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Detailed Answer:
Regarding the fact that things are going well in your life I would like to point out that anxiety doesn't have to be in the setting of a stressful situation, it is a question of neurotransmitter imbalance in the brain affecting mood. Long term benzodiazepine use may play a role, it does alter neurotransmitter balance, affecting levels also of other neurotransmitters such as serotonin and norepinephrine. As a result its withdrawal may disrupt that delicate balance and time be needed to find a new state of equilibrium. So yes it can be related. In addition its use my have covered an underlying issue which has resurfaced now.

As for the cold sensations associated with sweaty palms, they can both be a manifestation of the sympathetic nervous system, responsible for the fight or flight reaction. So anxiety does explain it well (whether preexisting or triggered by benzodiazepine use).
However some other possibilities of those symptoms should be considered, not necessarily neurological ones, but also rheumatologic like lupus or arthritis and hormonal alterations, in particular the thyroid hormone. For that reason some routine blood tests should be done in that regard to search for those conditions like complete blood count, ESR, antinuclear antibodies, rheumatoid factor, liver and kidney function, electrolyte panel, thyroid function.

Let me know if I can furthr assist you.

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Brief Answer:
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Detailed Answer:
Yes they seem to be thorough in their testing. As I said before the benzos do play a role, but often it is a combination of things, a patient being more prone to anxiety, benzdiazepine alterations, hormonal changes after menopaus etc which may lea to such manifestations in a prone individual. But one thing you should feel reassured about, given the normal tests and the character of the symptoms there is no indication of any serious disease, meaning of something which may be life threatening or disabling in time.

Wishing you good health,

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