I have been diving since 1979, and I'm just a few dives short of being a Master Diver. I have been out as a an assistant instructor many times, and I can tell you that you will do just fine. Just remember, if you forget everything else, don't hold your breath. Another tip - don't use to much weight. You want just enough so you sink when you exhale. To much weight will make your buoyancy hard to control.
I highly recommend that you continue your training to at least Advanced Open Water Diver. A few specialties would be good to, with Nitrox at the top of the list. Then maybe navigation. BTW, Nitrox will let you dive deeper and stay longer. One day about 4 years ago, I made 3 Nitrox dives in one day, all to more than 125 feet, and lasting 35, 25, and 20 minutes. (32 percent mix, 100 cubic foot steel tank filled to 3850 PSI) Though my dive computer told me I did not have to decompress, I did hold at ten feet until my air ran low. BTW, my dive computer was telling me at the end of the last dive to not dare go back in the water.