What Causes Redness And Soreness On The Foreskin Of Penis?

penis head red, sore, none itchy, tested for sti and all clear, doctors gave me antibiotics it cleared within 3 days but back by day 5. now been using canesten cream for 2 weeks, helped but not gone. still a little red. foreskin a bit sore. get rash on scrotum itchy then goes after about an hour.