symptom confusion

Today is cycle day 24, of a 29 day cycle. AF due 4/10. Tracking bbt, all week prior I was in the high 98's, yesterday I was 98.34, baseline typically 97.30. Past two days I've felt naseau, sore breasts, heavy breasts and tiredness. Today I took my temp before even getting out of bed and it's 97.58, naseau pretty intense this morning. Can anyone explain this dip? . BFN Saturday ( which was test day), haven't tested since.... anyone have symptoms similiar and get BFP?