Looks like you got the question asking part working, so maybe if you constantly ask yourself whether you are dreaming you can increase the likeliness of you asking yourself in the dream like you did that night. But even though that could be enough you can always go a step further by bettering your recall so that you are more likely to recognise that your asking yourself this within the dream, in other words have a little more awareness in the dream to answer the question. Improving your dream recall will help you improve on your awareness.