Hey there,
It just looks weak. My Zebrina did this last winter. Give it as much sun as possible, don't overwater! I wouldn't even fertilize unless you see the need to.
The Stem hasn't gotten enough light, thats why it is a light color versus dark green. The "odd marks" are normal, at least on mine. I'll try to find a pic or 2 of mine even though I don't think I have a good one...