No, you didn't test early. You can test as soon as your period is due.
False negatives are common testing early. It takes time for the levels of hCG to rise high enough to be detected reliably. For the best accuracy use ONLY your very first morning urine (wakeup pee).
If you still haven't had a period and are 7-10 days late, retest. HCG rises fast and it should be detectable by then. If still nothing, see your doctor.
Good luck, don't get frustrated. We don't begin to consider fertility problems until after a year has passed.
Hope it helps.