I am by no means an expert but with the little bit I've done and read up on, tempering is tricky, as different steels require different procedures/temperatures etc. If it was already tempered, by heating it you'd have likely taken the temper out to a certain degree. Doing it precisely generally requires use of a kiln to get the right temperature for the right duration, then whatever quench is called for.
Still, great work, nice craftsmanship. The even color on the blade coming out of the fire tells you it's very smooth and straight. Varying thicknesses produce different colors.
Wiley.