Who are you guys?
5 month old boston terrier
She's 4 months old, she's a baby, probably around 3 or 4 years old in human years. You need to treat her like that.
First, decide if you want her to potty outside, or in a spot inside. If it's inside then decide if you want to continue the puppy pads, or something like a Potty Patch. If you want her to potty outside then you need to stop providing her with a place to potty inside.
Whichever method you choose you are giving her way to much freedom inside. Remember how I said she was the equivalent of a 3 year old human? You wouldn't let a 3 year old have the run of your house without you watching him right? You'd have your draws empty, the scissors used in creative ways, amazing new inedible recipes started in your bowls, and the toilet plugged up because he decided to see if socks would flush. That's what your puppy is doing. That's why you childproof a room and use babygates when you cannot watch the child. Same with your puppy, if you cannot watch her then you need to keep her in an ex-pen, crate, or puppy proofed room. Doing that will cut down on the destruction by 99%.
For the housetraining, no more shouting no when you catch her having an accident. All that teaches her is that she should hide to potty since it's scary to potty in front of you. Again no freedom, no free access to the potty pads if you are going to let her potty inside. She should only be allowed to run around free when you are watching her, and then only after she's pottied. She should only have access to the potty pads when you are right there with her, and you should be. In order to housetrain her you need to be an active participant. You need to be right there with her when she potties ready to pop that tasty treat in her mouth when her little butt starts to rise when she's finished. Follow the instructions in this sticky thread House Training How Tos: it'll help you get on the right track.
For the destruction of your items, like I said, no freedom unless you are watching him. He shouldn't be alone in a room long enough to be able to totally destroy something. Exercise pens, and/or crates need to be used, or you can puppy proof a room, keeping him in those will save your stuff and not allow him to form a habit of chewing and destroying what he shouldn't.
What training are you doing with her, and what exercise is she getting? Keeping her mentally and physically stimulated will also help with her need to amuse herself by shredding stuff. Things like playing chase a toy and tug o war (don't play with her with your bare hands or encourage her to chase you), clicker training, chews, chase a flirt pole, and walks if she's had all her shots, will help tire her out.
It'll get better! They do grow up!
I'd suggest you kennel her or invest in an x-pen until she's old enough to be trusted in the house. That may not come for even a year and there is nothing wrong with that, so get something comfy for her!
It is actually fairly uncommon for dogs to actually chew on toys, except with the purpose of totally destroying them. Edible chews and food-dispensing toys are a better bet for giving your dog something that will be far more interesting than your lovely, smelly bath-mats and laundry. If I may so, it sounds like she is very intrigued by your scent, as it's mostly stuff like laundry and mats that she's going after!
The hiding her potties. Well, you did express your disapproval when she did business in front of you, so I'm guessing that she has drawn from that experience that she should be doing it in secret! No mystery there. For the coprophagia, you can purchase food and water additives that make the taste of the dog's faeces unpleasant (as apparently it isn't enough already :P ) and I hear that feeding pineapple will work as well.
Just. hang onto your hats. The best (*cough* worst) is yet to come, but a lot of it can be resolved by primarily management, and also training (yourself and your dog!). Nobody expects a whole lot of trouble with a small breed but a good handful of them are very smart, energetic, playful and mischievous! Pixie is an apt name. They are the sort of dogs that will happily create their own amusement should you not provide enough