Bro, go to GNC and get some Arginmax. Its a multi with extra zinc, E, and Arginine. Its not like viagra or cialis. It takes a while to notice the effect but there is definately one.
Also, switch it up. Check out the kama sutra online and give some of those positions a try. Some of those positions should come with a warning:
"WARNING - MAY EXPLODE ON IMPACT"