Something appeard on my arm skin

hello.
at first it appeared as pimple-like full pink growth . it was looking like a small bulb (1 cm wide and like 0.5^ cm height).
then it has started to decrease and left me something like a scar(?) one week later. its approximately 0.3- 0,5 cm wide and its not going away. really have no idea to comparie it .
please see photo attached and help :frowning:

could it be a dermatofibroma or any oskincanm

It may just be a small infection under a hair in which case it will gradually dry up and fade away. If it gets bigger and starts to itch then come back on here with another photo

Ok.
Thank you for answaer. Wish u nice weekend .