During my yoga journey of 6 years one thing that resonates with me is that yoga is not what we look about on the outside but how we feel on the inside.
The important thing to remember when practicing yoga is that YOU are the only one that will benefit or suffer. When we listen to our bodies (connecting to our breath, being present in the moment, and letting go of ego thoughts) we are able to move comfortably in our postures and receive the full benefit of what yoga really is - which is a feeling, not a posture. When we choose to push ourselves and effort in our practice, this is when we disconnect with our true selves, focusing on ego thoughts, and can cause physical and mental harm to ourselves - we begin to compare ourselves, judge ourselves and take our bodies beyond our physical comfort level.
During your next yoga practice see if you can be aware of your breath in each posture no matter what your breath is doing - just listen to it and feel it.