ovulation test negative next day

i have a bit of irregular period, where in 1 cycle i ovulate cd 19 n the other cd 22. not the same day always. i have noticed that i get positive ovulation just 1 day and its negative very next day. also its not that dark on days leading to positive test. so is it still worth it to try day after positive test if its negative completely? as in SMEP it advises to try 3 days in a row after positive test