Hi sir, welcome to health care magic, I can certainly understand your concern and worry about your hand practice, first of all dont get worry about that as it is a very common practice followed by many men , but i would suggest you to minimise that because it may lead to over keratinisation and thickening of skin over penis , that may obstruct with your sexual stimulation. I can advise you to control your urge by distracting yourself by watching tv, spending time with friends and look for some other alternative pleasures to come out of your stress and be relaxed. i can understand your another concern is that you are feeling fatigue and very fast loss, but by the information provided by you i can understand your age could be around 30 yrs probably, as this age is not at all the right one to make you fatigue in sexual relation , so this could be either because of your health condition and diet or due to some stress or depression . so please provide some more important information if I need to know. In the mean while ,I can advise you to avoid smoking and alcohol, maintain adequate weight, perform some pelvic exercises that which improve your erection, above all you can start drugs like sildenafil to improve your sexual performance by increasing nitric oxide (NO ) production. please post your further questions if any, I will be available to answer your queries Thank you