Hi Doctor.i Have Itchy Bumps On My Legs They Are

Hi doctor.i have itchy bumps on my legs they are like mosquito bites only iv had them for two months now and they wont go away.i went to a doctor who failed to diagnose them.im at my wits end.bcoz they are leaving dark marks.only a few appear at a time.when they heal I get them somewhere else still on my legs.please help me