It sounds as if this could be you then as you can"t do your old job but could do a different, I assume less demanding, job. "If you are unable, through illness, to work in your present job and your condition is permanent, you may be able to retire early and take your pension benefits without actuarial reduction. This is known as a Tier 1 (lower tier) award. "
Job seekers won"t give you anything as your savings are over 16k & you would need to be assessed as unfit to work by the DWP to claim PIP.