Fertility Treatments-Negative Pregnancy test period late 2 days

Hello So My husband and I have been trying to conceive for about 2 yrs.. recently I started fertility treatment and with this last course doubling my letrazole starting Gonal F and doing a trigger shot.. Well I was told to take an at home pregnancy test on Friday (day 14).. It came out negative.. I still haven’t received my period and I’m on day 16.. Have any of you experienced a false negative with a similar situation? If you have when did you receive your positive (around what day?)