You don't say what your physician's diagnosis was, and you're asking non-experts to diagnose your condition without seeing you. Will you be better in a week? How could we possibly know? There are a number of different possible causes for the pain you are experiencing. If you had pneumonia you would miss your ballet class and/or the competition, wouldn't you? Possibly missing them is better than not missing them and possibly causing more severe damage, isn't it? Miss these few now, or possibly miss a lot more later. Your choice.