Hey Chloe, I have had a similar experience. Meditation seems to make you better at meditation. It may make you calmer overall, but when you are very anxious no amount of mindfulness or deep breathng is going to help. 20 years ago there was a best seller called "Anatomy of an Illness" by Norman Cousins. He had the same experience as you but with a critical illness. But be careful with medical studies. Laughter is not proven to increase the chance of anything, it is associated with it.. Association is not causation. But I agree it is good for us.