Ejaculation problems symptoms and conditions

I started taking flowmax due to low flow and dribble. im 37 and never had problems like this before. Flow was great after a day on the flowmax. after a week it seemed to stop working. My doctor insisted taking 2 .4mg pills instead of one. 3 days later flow wasn't any better and my lower back and groin started to hurt. I stopped the flowmax and now its one month later, flow is better but my pain in my lower back and groin isn't getting better. anyone else have this groin pain? ive had no ejaculation problems but my wife has commented that im always tired and my sex drive has all but disappeared.