Ahhh I feel your worry! Honestly this happens lah, a few of us mum friends pernah kena situation macam ni, sometimes it's just too early and hormone levels belum consistent, atau the first test tu faulty je. Since you're already a day late, I'd suggest ambil test lagi in a couple of days or better lagi, check with your doctor so they can do a blood test, that one more reliable and won't leave you guessing. Hang in there, the waiting part is the worst