Lowes only carry the HPS and MH bulbs for those watt ranges, but not the balast to go with them. But yes, go back and get some CFL, compact Fluorescent lights. You can buy the fixture which means that you will have to do a little wiring, or by a couple hooded shop lamps with fixture and plug in all ready. These take up much mor room though. Keep the plants a couple inches from the light and get a small desk fan. Don't hope for fat buds, just chalk this up as some experience.
Adieu