For last 1 year we have been trying for baby and my cycles have been always regular. But this is the first time my periods are late by 8days till now. Today is the 38th day of my cycle. I have terrible back pain and feet pain. I am getting exhausted aswell very easily.  I had a spare test kit at home lying for past few months, so I tested with the same in the afternoon and found it negative. What do you think is the reason ? Am I really pregnant and should wait for few more days to test ?? Or is it something else ?? Please help.