I was on the pill. Missed a period. Did home test..negative. Was pukey (extreme), sore boobies (extreme). Missed another period so did another test. Negative.
Went to the OB/GYN a few days later. Did their pee test. Negative. Doc did a physical exam and blood test. Said I WAS pregnant and had time and the opening for me to get a vaginal ultrasound right there (had to wait around around about an hour). BINGO. Preggers.
In the end I miscarried (partial molar pregnancy), and a few months later was pregnant again..similar deal, on the pill again, negative pee tests at home and the clinic, but blood tests confirmed it. Miscarried again sadly, but for my final pregnancy (carried to term) neither me or the clinic bothered with pee tests. Just bloodwork to confirm it.
Hope things turn out the way you hope!