Was it proper to change lanes in this situation?

Why?

The video shows you moving from the left lane into the clear right lane. This is correct because you should keep as far right as practicable. When changing lanes, take extra care, signal and give way to vehicles already travelling in the lane you are entering.

art. 16 ust. 4 oraz art. 22 ust. 1, 4 i 5 Prawa o ruchu drogowym