It is possible to have a pregnancy test show a negative result 10 days after a missed period. This can occur because some pregnancy tests take up to 10 days after ovulation to show a positive result, according to Pregnancy Corner.
Early-Pregnancy-Tests.com explains that some over-the-counter pregnancy tests are more sensitive than others to hCG, the hormone which confirms the existence of pregnancy. Pregnancy tests confirm pregnancy when they detect a certain level of hCG. A less sensitive test needs a higher concentration of the hormone, and therefore a longer period of time, for a positive result. Some women also develop hCG at a slower rate than the norm; these women are more likely to need more than 10 days to confirm a pregnancy with an over-the-counter test.