When does BBT rise?

Have been taking bbt this month for first time. Cycles have been off since MC in Sept. Because I had no clue how long this cycle would be I have been doing opk much more frequently. This week did them 3x a day (morning noon and night). Yesterday morning and afternoon was very negative and evening was very positive. Ha a temp jump this morning for first time but opk has still been positive all day. Shouldn't your temp rise a day or two AFTER you I? And shouldn't opk be negative again before you O?