I'm sorry I'm just now replying it's been a busy month for me.
I hope all is well with your baby. At the time of your post you had only had her a few days so it was perfectly normal for to not eat as much during that time. Most go through a period of relocation stress where it can take a few days- a few weeks to settle in. I'm assuming she's eating like a little champ by now?
As far as the 10 min rule goes that is fine. I personally let babies eat as much as they want with no limits and start applying the 10min limit once they become juvenile/adult sized. Every beardie is different and just like us each one may become full quicker for that reason it's impossible to give an exact number of insects a beardie should eat. I'd say as long as she's eating anywhere between 20-100 insects a day she should be just fine. More importantly, as long as she is pooping regularly, gaining weight and not losing, and looks healthy than you know she's eating plenty.
It's also great that she wants to hunt. It's good for her and keeps her active. I have a very lazy spoiled dragon that expects me to hand feed her every time she eats lol. I try very hard to encourage her to get a little exercise.