I just realize today have been using bbt very wrong,I thought when it start making sound then it means I should put it under my tongue.it make sense why it’s always 35oc I was reading at Premom app it says when I wake up I should put it under my tongue and relax then when i hear the double beep in less than two minutes,it is done..but have been doing it the other way round..my period is late by 1 day..starting spotting about a week after ovulation,tested it’s negative used digital yesterday it’s negative..honestly ttc sucks and is stressful