started with neck ache, thought it was pulled muscle, 4 days later I have swollen scalp area and sensitive and sore, then next day after that I have swollen and sore lymph nodes on my neck and next day after that I got 5 red bumps on neck, like pimples, then next day I got 4 more on neck near same area....today my scalp and my red bumps itch and red bumps all have white heads. I was started on 500 mg APO-Cephalex2 days ago