Hi, I Had A Big Bruise On My Inner Leg

Hi, I had a big bruise on my inner leg just above my Knee. It was a huge and after the bruise start to fade away the itch started and it's still there, exactly on the same spot and the same shape but just itchy and my skin is red like i am having a rash. Should I take it seriously. I have been using DermAid which hasn't helped at all but I checked it the date has been expired... so I don't know what to do.
Many thanks