“Our universe is around 13.8 billion years old”
Problem: gravity bends time; and time is not a constant.
If you traveled at nearly the speed of light to the edge of the Milky Way and back again, about 40 years would have passed for you; but earth would have aged 100,000 years in that time.
After the “big bang” mass flowed out into space faster than the speed of light — which is theoretically impossible; unless, that is, time itself was compressed.
So how long did it take the universe to form? A trillionth of a trillionth of a second? And a minute more to coalesce into elements?
Space/Time itself doesn't need obey the laws of relativity. Space expansion can and actually does proceed at a rate faster than light. According to the Inflationary Big Bang model, the very early universe expanded at a rate many times faster than light. Then it soon after slowed down. Then, some time later, it began to accelerate again. However, this second burst of acceleration was much much slower than that of the inflationary period. In addition, there are supposedly galaxies outside the "observable universe" being carried away from us at speeds faster than light. The further a galaxy is, the faster it recedes, due to universal expansion. And remote galaxies can and do apparently recede at rates greater than light.
What is a year?