Mrityunjay23, as far as your spine is concerned it might be an idea if you got your doctor to refer you to a physiotherapist (called a physical therapist in some countries). A physiotherapist should be able to work with you on this one.

As far as I know there is no way of changing the sizes of the left and right brain hemispheres - they are set in the womb/early childhood.

Have you talked with your neurologist about the fact that your left brain hemisphere is smaller in comparison to your right brain hemisphere? If so, does s/he think this might be related to your symptoms and, if so, does s/he think that anything can be done about this in terms of your symptoms?