Hi Sophie, firstly your posts clearly show you adore your little girl. I have looked at your pictures of Bo and she's a gorgeous squidgy bundle and I'm guessing only around 10 to 12 weeks old?
You are obviously wanting to be the best mummy you can possibly be and sound very conscientious.
However, I feel I have to say, relax, enjoy and take some of that pressure off yourself!
Our Baxter is now one year old so it wasn't that long ago i was where you are - questioning myself, hoping I was doing the right thing and asking questions. It's been a bonkers year. We've had guarding issues, ruined slippers and poo's on the cream carpet! We've also had loads of fun and cocker snogs and luvin'.
I am no expert, but it sounds like a lot of Bo's behaviour is quite normal! The mad racing around i think every cocker owner has experienced. I used to judge this as Baxter releasing some pent up energy and would call him out into the garden for a romp around! Only for 10 minutes or so just to "get it out of his system." Once Bo can go out for for proper walks, i think you will see a change! She will come home and collapse!
After doing some training/play with Baxter i would want him to settle or play alone. I have always gathered all his toys away and each day give him a couple he hasn't seen for a while, or a new chew so he has a new interest to occupy him for a while.He does however, like to be near, so he would normally be by my feet and then fall asleep.
I have never used a crate but i do know from other Col'ers that they are supposed to be a safe place they enjoy, rather than a place of punishment. I am also not sure about the cereal packets and cardboard toilet rolls. i never wanted Baxter to shred and destroy. Do you not think this could lead Bo to believe it's ok to shred your mail, magazines and newspapers?
Anyway, Sophie, I am sure you are going to have a wonderful dog. The puppy stages are not easy, but your baby loves you and please don't be scared to interact with her. She will learn whats acceptable but give her some time to understand what you want!