I replanted my selloum in a new pot. It was in a planters pot. The leaves are yellowing. It only seems to be the lower, smaller, younger leaves. I was debating on the light amount, water, etc. I don't water often as it's winter in MD now. The soil is slightly damp, but not really wet. I have it about 3 ft from a southern window. Could this be stress? Not a good location? Help!