On reaching age 66 you may qualify for the State Pension. Subject to having a sufficient PRSI record, you should get the Contributory State Pension.
However it depends on what Stamp you pay. Your post suggest that you are a D Stamp (civil servant?). If that is the case then you do not qualify for the Contributory State Pension as you -presumably- were a member of the Civil Service Pension Scheme. The D Stamp is a reduced rate and does not include entitlement to a State Pension. You presumably get an occupational pension from the Civil Service Scheme?
In any event entitlement to the State Pension is not subject to any medical Cerys, but is subject to having a sufficient record of A (private sector employee) or S (self employed) PRSI contributions.
What is your PRSI history?