Your red spots is a fungus called Spot Anthracnose. The center of these spots eventually turn white, dry and fall off. Spray with a fungicide every seven days as long as symptoms persist. Avoid watering the plant from above, only water from base. This info. came from my better homes and gardens book. I do not know if your leaves will come back, but I wouldn't cut my flower back. Last year my yellow roses had Blackspot which causes leaves to fall also. I cut off diseased leaves but still had beautiful roses. Good Luck!