There are certain properties of your symptoms that would be key to understanding the cause. Are they persistent? Are they progressing? For the first question, the first thing i'd ask is: is your left toe still numb?

What do you mean by a twitch in your left eye? A twitch of the extrinsicl eye muscles themselves (e.G. Leading to blurred visions, disturbances in vision) would be suggestive of significant central neurological involvement. However, as I presume, if the twitch is elsewhere, like in the eyelids or the ring of muscle around the eye, this is less indicative of very serious conditions.

A progressing pressure headache can be suggestive of raised intracranial pressure, which your doctor will presumably have checked for with an opthalmoscope (to check for outward bulging of the retina, papilloedema). In the absence of this, a rapidly progressing neurology is unlikely.

A stiff neck and fatigue in areas of the body are, in the grande scheme of things, non-specific symptoms (could be a result of unrelated problems/anxiety). However, if they are indeed pertinent and your somatic experiences are indeed entirely left-sided as you describe, then there is the distinct possibility of neurological involvement.

Possible neurological conditions are: communication hydrocephalus (could be secondary to a tumour), right-sided silent stroke, right-sided tumour around the central sulcus. Lack of raised intracranial pressure would exclude a rapidly developing tumour or communication hydrocephalus - two conditions where speedy intervention is preferable. A silent stroke is a relatively common event, from which near-complete or complete recovery should occur over time.

If your symptoms progress/remain, consult your doctor.