When I started the breath awareness meditation many years ago, I thought I had a problem with my breathing. It was very fast, the in-breath was one second and the out-breath was one second. In one full minute I would breath 30 times. The teacher said it should be slower, slower. The average breath for adults, is something like 12 a minute, every 5 seconds a complete cycle. Mine was a cycle every two seconds. "Too fast!" I thought, "Oh I am a terrible meditator! I can't meditate right." For awhile I tried to force my breathing, which is not what we teach here. That didn't work because every time I didn't force it, then it was back to one second in, one second out, very fast. All of the sudden, after quite a few years, I realized that I had been a competitive swimmer for many years, my specialty was the breaststroke, in which the breathing is very fast. Up and down the head goes, in one second, out one second. I had trained myself to breath fast, my natural normal breath was 30 a minute. There was no problem. I thought I was doing something wrong, but actually there was no problem. My normal breath was simply not the slow one. Others can have the slow one, I've got a fast one, that is my normal breath. As soon as I realized that, I was quite relaxed. I just watched the breath at a fast speed, it was fine, no problem. The worry about my fast breath, the worry was the problem. Not the breath.
That is why with the way we teach, we don't care about what type of breath it is. If you happen to have a long breath tonight, fine, if it happens to be short, fine. Rough or smooth - fine. The awareness is most important. Tomorrow if it is opposite that is fine, too. Whatever it is, just sit there, whatever it is, you just observe it, in, out, in, out, rising, falling, rising, falling. Whatever it is, is fine. But to worry about it, that's the stress, that's the problem. If you see the mind worrying, then that is the mental noting time, we note "worry, worry." Then we come back to the awareness of whatever breathing it is.