Yes you are worried for no reason at all. The question as to the accuracy of a home test versus lab test as well as to the cutoff concentration of home tests versus the lab test has been asked over and over again every day. Use the search feature or scroll down the index of the drug testing forum and you will find the answer if you are still worried.

Don't be foolish and drink a ton of water on the day of the test. You may get a negative dilute for no good reason. Also, water is not the preferred fluid. Third, try to keep fluid intake around 40 ounces or less over 3 hours or you may be dilute.