I meditate on breath awareness as it seems simple enough and suits me well. I've noticed the past couple times I meditate that I'll be meditating, and I'll start to feel my body becoming more relaxed, and then all of a sudden I've nodded off for who knows how long. I will bring myself out of it as soon as I notice and raise my head up, returning my focus to breath awareness. I feel certain that this is because I actually lose focus in breath awareness and allow myself to get sucked in to mind's eye images, sounds, and the thoughts that are produced from them. Am I correct?