I dont really know enough botox but " neural therapy " in the tmj might be something worth looking into.

When your talking pain over the whole body , your really talking about something that sound more myofascial related to me , esp if its causing pulling on muscles etc.

Its hard to say whats causing what , as rule ( ive had range of things since 16 and im now 36 ) nerve pain ,as far as i know , doesnt usually cause tightness to happen in the muscles ( at least not the neuralgia sort ) so thats why im wondering if its more secondary .

Im not an expert though ( Mrs D would know a lot better than I ) but if I were you id try and rule out the possibility of things such as tmj by seeing if neural or even prolotherapist if the tmj joint is weak .

It might be you grind your teeth in your sleep or have strained the ligament there for all I know , but if you werent aware of it then you wouldnt know , as these things ( Proprioception ) is not something the average person can detect until it usually becomes a big problem and then triggers others .

Im not trying to scare you, just suggesting that things like tmj might have more brearing than you think given the skull / neck / spine are all connected.

Trigger point like neural is more of short term fix but at least it might give you an idea of whether a certain area like the jaw is being a catalyst in the sensations your experincing elsewhere.

m