irregular cycles..when to expect af

hi my cycles range from 28-32 days so i decided to start using opk this month to try and track my period...i recieved positive opks on cd 12 and 13...i did not take an opk on cd 14 but i did on cd 15 and it was negative which led me to believe i o'd on cd 14....well im now on cd 32 which is 18 dpo...goin off when i o'd i would think ill have a 28 day cycle..i took a hpt last night and saw a line but believe it was an evap because it showed past the time...could i still be pregnant or am i even considered late since tomorrow would be the latest af would come