This is to small and you will not need defoliation likely. Most leaves will be needed since there are few. Please give her more water when watering at this point. Pour water in a circle all around her. If she is dry and thirsty 1/2 gal is fair but possibly minimum quantity you should be pouring in. What it can hold it will run off. Out the bottom, remove the run off so it does not soak back in. She is shriveling because the root ends are dying as they hit the dry dirt. This is shocking the plant severely. Keep the nutrient intake lower and every other watering only. Just be sure once you water allow it to dry for days until the pot feels nearly dry again and the plant almost asks for water via minor droop. Then re water. At this point you cannot afford one more slow down in its life cycle. Good luck
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