Have I tested too early?

Bn ttc for 14 months and this month I was hoping that maybe things would be different.Last af was 2nd March, 28 day cycle and next af is due monday 29th. Today(9 dpo) I have bn having like twinges in my right side and the last two or three days I have been feeling rather warm. However I just took a hpt and BFN. Is this a definite negative? I used a first response hpt.