My dog's behavior is unusual and I don't know whats wrong?

My Dachshund is 10 years old, female. Her teeth were really bad at one point and she got an infection from them before having one pulled. When she was sick, she would constantly be at the either the garage or the front door crying at it, she wouldn't eat, and she would sleep outside by the AC on the rocks. After her infection passed, she was fine but lately she's been doing some of the same things. She eats, she does her usual routine and all, but the other night when I came home from work, she stayed at the garage door and cried. When I went towards the stairs where the front door is, she ran over there and did the same thing. She usually stays in the bathroom with me or my room when I get ready for bed, but she was missing for most of the night. I had thought she was sleeping downstairs on the couch, but when I went to look for her, she was sleeping outside in the cold on a lounge chair. When I got her inside for bedtime, she was unusually clingy to me, sleeping by my side with her head on the pillow. Since then, she has to be near either me or my father and if not, she goes outside and sleeps on the lounge chair. She's been doing this for three days now and I'm not sure what its supposed to mean. She hated sleeping outside for first 10 years of her life (shes turning 11 in February) but all of a sudden, she constantly goes out there and doesn't come in, not even to eat. She will eat if I'm there and I offer it to her, but will not on her own. Oh, and a big part is that before she got her teeth pulled, she had the worst odor in her mouth. After her teeth got pulled, it never smelled. All of a sudden, her breath smells foul again but her teeth look fine. Also, a month back, she lost the top row of teeth in the front that the vet said could happen due to the one tooth being pulled and there not being support for them, but I'm skeptical about that. I'm lost and I'm not sure what to do. I know she's getting old but this is too unusual for just old age.