I'm 50, healthy, married 20 years, in a relationship and with a good sex life. Over the past 6 months, however, I've been bothered by swelling and small blisters on circumcised skin behind the head after unprotected intercourse (vasectomy years ago). Healing is taking longer, now up 10 days. I've tried condoms with extra lubrication added. Not much help. Any ideas on what may be causing this problem. Any suggestions on how to minimize this friction? thanks, radio.