bbt alternatives?

Ttc # 2 for 2 years. I really want to start bbting again. I did about 4 years ago ttc my son. He is now 2 n a half. But gets me up at 5am every morning. I dont wanna set an alarm, it will wake dh. He works long hard hours n Im not about to chance waking him up. I have a bbt thermomiter n thought about temping litteraly as Im getting up to go get my son. I know it may not be as accurate but is it my only option? My cycles are so unpredictable lately n opks unpredictable and wonky as well. Anyone else do something similar or have any suggestions?