The sense of time had always been strange for Quinn. He had lived most of his young life as a human, but after that he had experienced many things that changed everything. Perhaps it first started when he lived through Vincent's life.
During that time, he wasn't just shown memories of his ancestor Vincent, but went through it as if he was actually there himself. Still, since he wasn't in control of what was happening, it never felt like he was the one making decisions.
After that, Quinn needed to grow up quickly, as he was put through test after test, war after war, and enemy after enemy, all for it to fall on him as he went into a deep slumber, one that managed to last a 1000 years.
Even after waking up, Quinn had gone into the celestial space, a space where time moved far slower, to the point where it was almost non-existent on earth for a while, and also had created his own space where time slowed down so he could train on his multiple powers.