Dear Welcome to HCM We understand your concerns I went through your details. Erectile dysfunction (ED) or impotence is sexual dysfunction characterized by the inability to develop or maintain an erection of the penis during sexual activity. You have not mentioned about your previous experience with the same woman or other women. Usually, Ed is psychological. You also say you had acidity complaints during the intercourse. I also think you were too stressed and anxious. The most important organic causes are cardiovascular disease and diabetes, neurological problems, hormonal insufficiencies and drug side effects. I suggest you not to panic now and wait for a week before attempting next time. Then you can decide on consulting a physician. If you require more of my help in this aspect, please use this URL. http://goo.gl/aYW2pR. Make sure that you include every minute details possible. Hope this answers your query. Available for further clarifications. Good luck. Take care.