I have had this cast iron plant for many many years in the exact same spot, no fertilizer, and it has done ok but not a lot of growth. I decided to take it out, change some of the soil, and trim the roots a little. I returned it to the same spot. But now, the leaves are turning yellow and it has some brown tips. The pot doesn't have drainage and my housemate watered it again when it probably didn't need it. Are these all symptoms of overwatering or could it be transplant shock?