Hello, rather embarrassing issue to discuss, im 25, im in great physical condition, i work out daily and take care of my body, i eat clean whole foods, and are very, very attracted to my girl. I also work long hours out of the day, my job isnt very stressful, but the hours are long. Sometimes, i find my self just worn out, completely out of energy, and just cant keep it up for the simple fact that my body is just beat. Other times however, like a weekend, when im full of energy, i just cant stay erect. Most of the time ive noticed that its when shes on top and im on my back, and i slowly fad, i try to flip her over and take over from there when i feel like that is happening, but most of the time its just too late i loose what ever erection i had and just blame it on the fact that im tired. I know she would never say anything to make me feel embarrassed, but i can tell sometimes when that happens shes a little disappointed. Sometimes im like a brama bull and she has to tap out because im too much for her, and that's how id like to keep it, but the more this keeps happening i fear the more it will begin to take a toll on our relationship and that's something i don't want. I dont think its a mental thing, i have a good deal of confidence in myself, but the more this happens i think i will begin to take its toll on me, im writing a post about it so i guess it has already taken some kind of toll on me. I think it may be a circulation problem, maybe, sometimes i just don't get great blood flow down there. when i have taken stimulants like stiff nights or Viagra, i do just fine, obviously, because it stimulates more blood flow for a stronger erection. can any one help me out with a reasonable answer, ive done and still do the whole kegal exercise thing, i have been for years just for the simple fact that it helps you develop more control in bed, but its not helping me maintain and erection. Id like maybe some advice or help with this problem before i go to the doctor and complain about erectile dysfunction at the age of 25...