Don't make the mistake of judging size by what you might see in sexy magazines or movies. Like the women, the men who pose are well above average. Compared to them, you may be small, but compared to most men, you're right on the mark. Second, size has little or no correlation with amount of pleasure a man can give a woman. When it comes to making love, technique and passion are they keys.
Size is unimportant.
If prescription drugs or alcohol aren't the problem, look to stress enhancers. Something called the Kegel for Men is catching on as a natural way to strengthen erections. The Kegel is easy to do. Squeeze the muscle of your pelvic floor. They're the muscles you use when you try to stop the flow of urine.