If there is, it wouldn't be good for you. The reason you can't is because the tissue inside the penis is very sensitive. If you don't give it enough time to return to normal, you can risk damaging it's functions over time. That's why it's hard to get a second one, natural process of the body to protect it.

There might be some natural ingredients that are used in gaining erections, that if you had more of you might be able to rebound faster. Stan gave you a warning of why, so perhaps you should research that more first. Otherwise, your body uses things such as L-Arginine, Nitric Oxide, Testosterone and 5-alpha-reductase to turn that into DHT, cGMP, choline, etc for erections and sexual health. Zinc is probably also beneficial to sexual health as it is to sperm. 50mg is the upper limit one should take and that counts what you get from your diet and supplements together.

In simple terms, Protein and Lecithin are the best options to give you the above.

Oh, and just to clarify a bit this is what is going on. Remember that the penis doesn't really have a constant blood flow like the rest of the body, thus why you have nighttime erections every night. The tissue needs to remain alive. When you get an erection, the tissue fills with blood, which is then blocked from leaving by the muscles and such. Thus, it's basically like your penis is, I know this sounds silly, holding its breath. Try doing that for about thirty mintues and you'll see why it needs a break.