confusion!!!

hey guys and girls...... my wife and I are in complete confusion.. I am now currently 17 days late for my period... I my last period was 31st August we have two very faint early pregnancy tests but on October 2nd hcg neg now two weeks on from that still no bleeding or any sign of it being due :/ have the symptoms ... tiredness, sore boobs and lightly nauseous.... has anyone had this and later found out thay the are infsct pregnant?? I also have pcos but its never effected my cycle before however I have read it can have an impact on hgc tests and that women only got actual answer with ultra sound... can any one help of give advice?