Chloe's back legs seem to swell up around her fetlock/pastern area lately. She's not lame, no heat, the swelling is squishy and they seem better, if not totally gone if I ride her. They only swell up if I haven't ridden her in a day or two or if she's been stationary all day (which is usually the case, they're in sacrifice paddocks for the winter eating from round bales). She had to stay in for the past three days due to ice and they seemed extra swollen. I lunged her and they were basically back to normal. Is she just stocking up? Or is this something I need to worry about?