Defined Reddish mark on pointer finger

i first noticed this mark on my finger on xmas eve and over the past week its gotten bigger and we from looking like a square to where the bottom is at an angle.

i am a huge nail biter and i wouldnt put it past me that I bruised it but i cant recall exactly what happened that would have cause a bruise this shape or why its growing. id like to rule out melanoma as it isnt developing in a single stripe but im still nervous.

pic 1 and pic 2 and about 4-5 days apart.

I think its just damage to your nailbed. It will grow out eventually but may take a while.