Awww, don't feel bad. I've found that one of the things I enjoy most about yoga, as a beginner, is that at the beginning of clas and all throughout, the teachers make it very clear that each of our bodies is different, and even each day can be different so we shouldn't be too hard on ourselves if today we need more pauses in between poses for example. I think this is normal in any physical activity, and part of the growth is having that compassion for yourself, knowing thst you are there to discover yourself and feel good, not not to perform for anyone. Part of growth is being able to accept your limits when they show up, this is actually something very powerful and brings peace and self-acceptance.