Aih, ini memang bikin stress kan! Nine days delay dengan negative UPT tu boleh jadi banyak sebab, stress, hormone changes, weight fluctuations, bahkan infection semua boleh affect cycle kita, especially kalau biasanya punctual. A few of my mum friends pun pernah experience ni and it turned out nothing serious, tapi since yours is so irregular from your normal pattern, I think better you see your doctor to be safe, they can do blood test or check if ada lain-lain happening. Jangan worry dulu, sometimes our body boleh surprise kita je!