DP and I have been trying for our second baby for the last four months or so. Every month before now, my menstrual cycle has been like clockwork. Normally I have a bit of a show before it arrives on the exact day it's due (28 day cycle). However, I was due last Thursday and there is still absolutely no sign. I have tested three times now. Twice with cheaper tests and once last night with a ClearBlue digital. Where is it?! And at what point do I book a doctor's appointment?