Neurological symptoms needing a diagnosis..?

I am a 42 yr old male, desperately looking for answers to symptoms that I'm experiencing: starting over the last 3 months. I would be most appreciative of your comments and opinions on the symptoms I describe below:

3 Months ago I had intense pain deep in the left shoulder which radiated down left arm. This has subsided very slowly over last 3 months and although not completely gone, it is only a shadow of the pain it was initially. 

At the same time as the above, the thumb on left hand began to twitch. The twitching ceased after a couple of weeks, however I noticed that I could feel the tendon in the crease of my left hand between thumb and forefinger - it is very pronounced and although it doesn't look much different from the right hand, to touch it you can clearly feel the difference - as you cannot feel the tendon in the crease in the right hand at all.
I have examined both hands closely and it appears that there may be a very slight sign of atrophy on the left hand as opposed to the right but it would probably not be noticeable to anyone else...
Also on my left hand, the thumb knuckle and left little finger knuckle produce an aching pain when tensed. This has remained the same for the last 3 months. However there is no weakness.
In the last few days my right thumb has began to twitch (up till now all hand symptoms have been confined to left hand). Also in the last few days I have stiffness and aching in my left wrist and up the underside of my forearm. I also have a stiff ache in my right ankle and up my right calf.

Another symptom that started 3 months ago is a twitch in the lower lid of my right eye. This is intermittent but happens everyday. Over the last 3 months the intensity of the twitch has decreased but it remains present (and is twitching as I write this).

2.5 months ago I started having a very noticeable intermittent 'buzzing' feeling in my feet. Both feet 'buzz' but not usually at the same time. The buzz is through the centre of the foot and around the ball of the foot just back from the toes. This was very intense initially and is still present on and off on a daily basis but has subsided in intensity.

Also 2.5 months ago I noticed an ache in my left big toe, especially if I place pressure on it when walking.

3 weeks ago I noticed pain from the outer blade of my right foot across the top of my right foot and to the ankle. This is only noticeable when I roll onto the outer foot when walking and remains the same today, however as I mentioned above I also now feel a stiff ache in my right ankle and up my right calf.

I have also experienced tremors throughout my whole body on occasion over the last 3 months this usually happens late at night whilst laying in bed.
A new symptom from the last few days is a twitch in my left upper thigh.

The last point to make is that I had a rash which started approx 3.5 months ago (before the first 'neurological' symptom of a twitching thumb) - it affected most parts of my body including the trunk, chest arms and legs and presented as a lacy mottled rash - most intense on my arms (the underside of the arms). A dermatologist I saw described it as Levido Reticularis. This still comes and goes with a mild burning and inflamed sensation. Not sure if this is relevant to the above but thought best to include it. 

I was referred by my doctor to a neurologist who examined me and sent me for an MRI of C Spine for which I am awaiting the results. However from all the reading I have done I cannot see how an issue with the C spine could explain all the symptoms above. 

Once again any appraisals, opinions or points of wisdom that can be handed to me at this point would be gratefully received.

Many thanks for taking the time to read through.

Alex