Adam's creation was the sixth day, right? You can count the age of the Earth on your fingers, then.
The term day is used three different ways in the creation account itself. 1, being the daylight hours, 2, being the 24 hour period, and 3, being all the six days combined in one day. The seventh day continued on in David's, day, then Paul's day and still in our own day. The seventh day is still going on. (Psalm 95:11 / Hebrews 3:16-4:10) The Hebrew term translated as day can be any amount of time from a few hours to time indefinite. Judgment day lasts a thousand years. The evening and morning in the creation account aren't literal days because 1, those periods only constitute a half a day and 2, there were no human witnesses on Earth those days would have applied to and 3, the only witness to mark them were in heaven where they wouldn't have literally applied either. The evening period was an unknown period of time in which the angels who anxiously watched the creation were unable to see what was going to happen and the morning was when the creative acts were revealed to the angels in stages.
Anyway, the first of those days, or creative periods, didn't begin until after Genesis 1:1 when the heavens and earth were already complete. The creative days were only progressive stages for making that completed planet habitable, so they in no way constitute the age of either the heavens or earth.