I took zzzquil Wednesday night, Thursday morning I took a digital pregnancy test. I got a positive result. Took another test Friday and got a negative result. Could the active ingredient Diphenhydramine HCI . Create a false positive? I tried researching it but, all the topics only talk about a drug test not a pregnancy test. Did anyone else have this issue and btw my Aunt who is a labor and delivery Nurse, she swears I am pregnant. My period is due in 3 days. My Husband and I are hoping it's positive but, I guess I am not as optimistic as he is