Here is information about the description and causes of the premenstrual syndrome from wiki.
This is a good video taking about SPM.
Dancing requires an optimal mental and physical condition, this ideal situation is for 3 -8% of woman a less probable scenario. If pain appears without explanation you cannot assume that it is PMS at all, just pain in my opinion, dancing should be performed as slow as possible until fun is achieved.
I hear that ripe bananas have antiinflamatories propeties whichs can help you to reduce general pain, in this case in particular because you have no idea what could be the source of it, for example muscle stiffness can have this list of causes. This article from Medical Daily talks about the benefits of eating bananas. I do not believe in a complete release, just let it go slowly and stay relax. Please, do not exaggerate eating to many bananas, it is just when you feel abdominal pain, not everyday because too much has others consequences not desirable such as constipation.
You should decide when to stop you dance routine because it is not fun, instead go better for a walk.