BBT question

Whitney

I woke up at 6 at my normal time to take my temp but it was really low this morning. Our house was FREEZING cause my fiancé turned the AC on last night 🙄 so I went back to bed and woke up at 9am and wanted to take my temp again and it was back up to 97.58?? Should I just count on this morning temp and say my period is coming? I don’t have signs of her at all