Sometimes after a gentle yoga class in which we do a lot of back openers and an inversion or two I feel kind of anxious for most of the day. I am on medication for a panic disorder, but this type of practice sometimes causes the above. When I do a yoga flow class this does not happen. Actually one day my yoga instructor told us at the end of the practice that whqt we had done could make us kind of emotional that day, and it surely did! What happens to the nervous sytem during and after such a class??>
Please, excuse the delay in answering you.
Back bending is related to let go fear, to trust in your balance and equilibrium. This can be the reason why you feel very emotional, because relates to the panic attacks.
If I were you I will avoid them for now, talk to the teacher and explain that it is still difficult for the moment to do those exercises. That does not mean that you will never be able to do them. If you keep practicing yoga it will bring you confidence and you will slowly build enough strength to change that condition in a short-medium term.