Sorry, but this doesn't make any sense.
Speed (including light speed) is non-directional. If it had direction, then it would be velocity, not speed.
For example, a train going 50 m.p.h. north is going the opposing velocity of a train going 50 m.p.h. south, but both trains are travelling at the same speed.
Speed goes from zero to "C" (according to Einstein) ...but there is no negative speed. Light cannot travel backwards... If it tried, it would just be light going in the opposite direction.