Hi Lisa, congratulations on the birth of your daughter Zali .
AFAIK corrected age is the age that our baby would have been had she been born at term. For example when your daughter is 14 weeks old her corrected age would be 7 weeks. I think they mainly use corrected age to measure milestones so that you don't have unreal expectations ie you might read that a baby will first smile a x number of weeks but in your daughters case it may be x weeks plus 7 before she can be expected to reach that milestone.