I adopted a mutt from a shelter about 4 years ago. She is a 5 yr old Hound, German Sheppard, and Retriever mix. She has never really been afraid of anything. Especially at home. I came home from work the other day and found her in the bathroom with the door shut (this has never happened). She has been panting, shaking, and not leaving my side for a two days now, and it gets even worse when I have to leave or when I come home.

The only thing I can think of is that it might have been a noise, but this is not really plausible. I live in Chicago in a 1 bedroom apartment, so she is pretty numb to any startling noises. I even checked with my landlord to see if someone had to come in unexpectedly and may have scared her, but he said no one has been in there.

I don't know what to do at this point. I want to console her, but I feel like this may lead to bad habits every time I have to leave, and she has to be OK being on her own during the day. Some people suggested a thunder shirt, but I feel like this is a temporary solution to a bigger problem. I'm trying to get her back to normal. Any ideas would be helpful!
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The door opens inward, so it is possible she could have closed it on herself. I guess my question is if that was the cause, why would she continue to be afraid of every little noise once she is out for a few days? I could see it causing her to be scared of the bathroom then, but not the whole apartment.

By all means console her! You would want to be consoled if you got locked in a room. She probably did close the door behind her and freaked out, thinking you were punishing her, or someone was. She can't 'think' through the door closing nor all the other rooms, and what this all means, especially if she thinks someone was punishing her. Spend every possible moment cooing over her and hugging her, and letting her sleep with you, and so on. Maybe even hire a dogsitter for a while, or take her to a doggie day care. Buy her some special treats too. Really coddle her.

I have to disagree with Joy. Consoling her will give value to her fear. Dogs aren't like humans, they don't need to be consoled about something that happened in the past, it will, like you said, cause even bigger issues. By consoling her when she's afraid you're telling her that she has a reason to be afraid, and she'll be even more afraid.

No cooing, no hugging, no letting her sleep with you. That's what you'd do for a child, but not for a dog. Very bad advice indeed. DO NOT CODDLE HER! I can't stress this enough.

Sadly you don't know what's causing this fear, which makes it hard to give advice on how to stop this fear. I would hire a dog behaviorist, someone that can come into your home and see what your dog is doing, how she's reacting. It's very hard to give advice about this online without knowing what her fear is.

Good luck.

I don't get it. I have consoled dogs and one cat with good results, not knowing what pet experts say. Where does that theory come from?

It's actually not a theory, it's a proven fact. If a dog has a traumatic event, and you coddle the dog, do the "Oh, sweetie pie, it's okay, come to momma" voice, the dog learns that he has a reason to be afraid. It intensifies the fear.

Hugging, kissing, cooing, treats, that works on humans, but dogs are very different from human beings.

Now, having said that, I'm not saying that you shouldn't protect your dog from things that scare him, or could injure him, but making a big deal of something that the dog is afraid of, is not a good idea. Many people don't like Cesar Millan, but there are certain techniques he uses, and has used, on fearful dogs, that really do work. His number one rule is not to coddle, or be overly sympathetic with your dogs fear. He once worked with a great dane that had fallen in the kitchen. The tile floor had been recently washed, and he had quite the fall. They called Cesar because after this incident the dog was terrified to walk in the kitchen.

Cesar asked what they did when this happened. The reply was "I ran to him, asked if he was okay, hugged him, held him, gave him a treat, told him that the big scary floor wouldn't hurt him". So Cesar said "You treated him like a child then. Well, he's not a child. When you did what you did you taught him that he should be afraid of the floor, otherwise why would you react that way?"

It took some time, but with positive reinforcement, and no more "Oh poor boy" tone, the dog learned that he had nothing to fear from the kitchen floor.