Is it possible that a couple tiny red dots (not blisters) on underside of penis that only lasted 3 days were recurrent genital herpes?
Probably not. Almost certainly this isn't herpes, which doesn't cause "red dots" that don't become blisters or open sore. And no herpes outbreak can heal entirely in only 3 days; 7-10 days is the minimum. If you have been diagnosed with genital herpes, follow your doctor's advoce about management. If worried about herpes but not diagnosed, the "red dots" don't suggest you have it.