What Causes Pain And Black Scar On The Needle Prick Point In Hand?

age 35 80kg 177cm i went for blood test but the nusre place the needle wrong place or what i don't know but i got pain blood flow very low after that i fainted . after 10 miniute take from other hand this tie know problem . but now i feel the first blood taken hand like no power and pain and needle that area some black scar one inch area .this hand not fell like the other hand. pls tell me what to do . is it serious .