Problem with skin please help??!!?

ok so i have a problem a have a dark mark around my nose its not all over its on the sides of my nose and i dont know what could have caused it since i dont suffer of sever acne just one or two pimples durin my period but this has gotten worse day by day does anyone know how can i remove it with home remedies or what can i buy to get rid of it thanks in advance hope someone can help me!!!!