It definitely is possible to receive a false-negative result on a home pregnancy test. Some things that can cause a false-negative result are not following the package directions (especially the ones that say how long to hold the dipstick in the urine) and testing diluted urine (such as if you drank a lot of water during the day you tested). Testing first thing in the morning is a good idea because that's when your urine is most concentrated.
Your best bet at this point is to see a health care provider for a more precise pregnancy test in a medical setting. While you're waiting to do this, be sure to live as if you are pregnant -- in other words, eat healthy, don't smoke, and avoid drinking alcohol. Until you know for sure, you should err on the side of caution.
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