Please don't think of getting an Ecollar and hitting the button when your dog is doing these things you don't want her to do. You're liable to make some of the problems worse.
You can use it to improve her OB, as it seems that when some distractions are present, she doesn’t obey. Many beginning OB classes don't address distractions.
The shadow thing, as some have mentioned is similar to OCD in humans, and is not a reason to use an Ecollar.
If you decide to work on the dog's OB with the Ecollar, I suggest the Dogtra 1900 or 2300 and MY METHODS