If you have the time, load for 2-3 days before your schedualed test. The test at WalGreen are very dependable. But, by the time you buy Creatine and home test, it's probibly cheaper to buy some substitute urine. Plus, by substituting, once it's in the cup at an acceptable temp, you've passed. No waiting and wondering. Go buy a $.99 travel size bottle of shampoo, rinse it out throughly, fill it with warm water and start practicing. I believe you'll be amazed at how easy it is to maintain the correct temp for hours this evening while you watch the hockey and basketball playoffs. Then if your still nervous about the tiny possibility of an observed test, plan to substitute, but load up with just water and vitamins as a back-up plan B. N2