Just wondering but why are you still in a postdoc position? My previous field was Medicinal Chemistry and had I continued with my Ph.D, I would have gotten it by 26/27. Post docs are usually for 2 years in Med Chem I believe.
Start school at 7;
Start university at 19;
Start PhD at 25 [4-year bachelors + 2-year masters] if you can do that immediately after masters, or 26;
Finish PhD at 28, or 29 (if it's a 3-year PhD, otherwise older);
Finish first post-doc at 31, second one at 33/34.
By mid-30s you are just starting your tenure-track (assuming you get some semi-permanent position at a university or research institute)
I'm currently doing a PhD [quantum chemistry] and this is basically my expectation for the future.