Light changes energy during reflection or refraction. However it maintains its constant speed. The change in this energy is detected as a change in the frequency and/or wavelength.

Does speed change in refraction?

This change of direction is called refraction. When light enters a more dense substance (higher refractive index), it 'bends' more towards the normal line. The amount of bending depends on two things: Change in speed – if a substance causes the light to speed up or slow down more, it will refract (bend) more.

What happens to the velocity of light during reflection?

So, as the reflection takes place in same medium therefore there is no any change in speed of light but refraction takes place in another medium therefore the speed of light change its path and hence get bend while entering into the another medium.