Hi. I have had a stretch mark on my stumach for a while now it is white and can hardly be seen. i work in care and was kicked in the stumach where the stretchmark is. it has been 3 weeks and two days ago i noticed a small red lump inside the stretch mark. only about a cm in diametre. it doesnt hurt just looks quite angry. its squishy to touch. Today it was black. i squeezed it and a little bit of blood/puss came out then it just stopped. its still black however it is no longer raised. what could this be? do i need to seek medical help.