Before I came along these practices I was meditating with an app called headspace. During my meditation they let me focus on my breath and count it.
Because I learned it this way I have somewhat of a problem letting go of the awareness on my breath. I often find the mantra synchronized with each exhale and inhale. When I try to let go of these thoughts about they keep coming back and I find myself focused on my breath again, never on the mantra itself but always a combination of mantra and breath.
This often gets frustrating during my meditations and I can't help but feel that this not the way I should be meditating.
Is this normal? Maybe it's just a longer process that stretches over multiple meditations to get rid of this habit.
It can happen that the mantra will synchronise with the breath for a time, or with the heart beat, or with other rhythmic patterns in the body. It is not important, and is not something that you have to prevent from happening. All you need to do is to follow the meditation instructions, which are to easily favour the mantra with your attention, over anything else going on. If you notice the mantra has synchronised with the breath, then simply treat that as any other thought or perception arising in the mind, and favour the mantra with your attention.