Abby, you need to treat the plant probably two or three times (better) within a week to be sure to get all the mealy bugs. New eggs hatch and the tiny nymphs hide in the leaf axils so if you only treat once, you almost always have a re-infestation quite soon.
Use a spray of 1/2 rubbing alcohol diluted with water. Spray very thoroughly - everything dripping - each time. Stems, undersides of leaves, soil surface, everything.
Your plant may go dormant in response to the short days even if the weather remains sunny. Your sun room sounds like an ideal winter home for this plant, though. In spring when you see new growth starting, you should probably invest in a larger pot, fresh potting soil and get that baby into more room for next summer. Your watering chore will be a lot less with a big enough pot. I always recommend you choose one that is a light color, which helps keep the roots of the plant cooler if the sun shines on the pot.
