My daschund is turning four this Dec. 15, and she's having problems that aren't becoming of her personality. Meaning, she used to be active, and very energetic, but nowadays she's very lethargic, and has a habit of "sitting" everywhere. I hope it isn't her back, but I can't find a lot of information on it - she's overweight, but not obese. She's merely quite plump. What should I do? What's going on?