Major drop in bbt 10dpo. HELP PLZ!

First month charting. I can’t edit my chart for some reason but actual ovulation day was cd 49 as I got my first blazing opk on cd 48 (I’m irregular) and today marks 10dpo. Temp back down to 97.49. Think af is coming or should I not let one temp get to me? Could I still be pg? I’m new to all of this.