16DPO and no sign of AF

Today is my 16DPO and no sign of AF.  Late last night when i took shower i found brownish spot while i was checked my cervix position.  it's still high and closed. At first I said to myself tomorrow i will have AF.  Today AF is not show up yet and I just recently check the CM and just dark brownish spot.  I do not know if the brownish spot i found last night was implantation bleeding or not.  dare not to hope....

i will see by the end of today if AF show up or not.  If not then I have some hope there.  

Will update the info later.