Are you having rest days? Rest and recovery are a pretty vital part of actually seeing any benefits from exercise. Especially since you’ve got a physically demanding job, your body might be crying out for some recovery time. If you really want to keep the habit of daily exercise, you could try splitting some of the activities out to alternating days, so you could still do some gentle yoga and stretching on ‘rest’ days, but only do the cardio and core on alternating days.