I have a new prickly pear that I love and it just went limp on me tonight. I checked the soil and it feels moist but not wet and top inch is bone dry. Around the roots is a little damper. The top stems are wrinkled and limp. Is this a sign of over or under watering? The plant is bright green with a few brown spots which most of them they had when I purchased the plant. I did also put it in a really 12"w pot on the advice I should go a bigger in anticipation of its growth. The plant gets full direct southern sunlight.