7days late test negative

Im so confused Im 7 days late now I took a test its negative but I was going through my period cycles from March an there all different like march I had a 23 day cycle, april I had a 20day cycle,may I had a 21 day cycle, june I came on twice first cycle was 24 day cycle an second one was 25 day cycle then july I had a 19 day cycle then August I have 22day cycle my last period was 7th aug to the 12th August an was due back on the 28th of august but nothing yet ?