Our GP's are excellent at dealing with common illnesses and general internal medicine issues. Unfortunately, they can't be experts on all things and may not keep up with the most recent guidelines on diseases such as MS. I would definitely ask to see a neurologist, preferably one who specializes in MS.
It is completely possible to have the symptoms you are describing. Numbness does not need to be limited to one area at a time. With all that you describe, you need to have an MRI scan conducted with an injected contrast agent. There are other tests to identify nerve damage. Testing the spinal fluid can also provide evidence of demyelination in the central nervous system.
I do think that you should see a neurologist. Good luck
Mel .. First I am amazed that they simply are not following the worst guidelines from 10 years ago which were pretty stupid .. an MRI sgould be done , you can have a GOOD opthamologist look at your eyes for the signs of MS as well but taking a sample of your spinal fluid will also be telling .. by the way you are spelling I am guessing you are across the pond which I find amazing since most of our info and research comes from there so how do you get YOUR doctor to pay attention : Demand it or Get another doctor and with all the MS foundations abroad I am sure you will have you dx (diagnosis) very soon .. good luck !