Ipill, period related. Pregnancy again?

Expected ovulation day as per tracker was 28th aug. Had unprotected act with withdrawal method on 24th. Withdrawal  method had somewhat failed. Had 1 ipill on 26th, after 32hrs. Cervical mucus  remained clear and stretchy till 28th aug , from 29th it became white and sticky. Had arrays of discomfort for the next 10-12 days. Ranging from cramps, back pain,  fatigue, bloating and gas, breathlessness. Did a HPT on 08th Sept, came negative. Currently  on 9th Sept, gas has gone but fatigue and breathlessness remain. Chest feels fuller and little sore on sides.  Have visibly gained weight and lower abdomen feels harder and fuller. Also there is quite an increase in cervical mucus which is white, creamy and odorless. I'm expecting my periods on 12th Sept (as per tracker, not considering ipill). Since I had a negative hpt on 8th, is there still  a chance of pregnancy or is all this discomfort due to the ipill? Do I need to check for pregnancy again?