If you become disabled before you hit full retirement age (you can't get it after), here is what would happen.
Let's say you took early at 62. At 63 you became disabled. You filed and won that claim. All the months after the first 5 of disability, would be payable as full reitirement, but reduced by ONLY the amount of months you took early that were NOT disabled (as retroactivlely found). So, for the 12 months of taken early retirement from 62-63, plus the 5 months after 63 that you were first disabled, you'd have and keep your early reitrement benefit and not eligigible for the difference between that and your full retiremenet. However, from 63 and 6 months, those would be disabled months of entitlement. THe reduction you took due to taking at 62 would be adjusted because it was no longer true that you took 4 years early, but only 1 year and 5 months of early retirement, the rest being NOT. So instead of being hit for 48 months of reduction, you'd see 17 months worth, which is quite a bit less.
Keep in mind too that working each year now, may increase your benefit anyway - they look at the top 35 years, so if this new work you do bumps another older year off, inserting itself as now one of your top 35 years, that would increase your benefit too - at least incrementally.
But the most obvious way to increase benefit is to not take early. Live off of work earnings and wait til 70 to retire. That gives you an 80% increase over if you took at 62. And a 32% increase over if you started at 66.