Barking

It sounds like you are doing a good job bonding though. And that is awesome. But most often, yes, barking is a call out for company. You may be paying her a lot of attention, but you need to remember HER most active hours are AFTER you go to bed. So as much as you play with her, there is still a lot of time she might be feeling a little lonely. They are VERY social. Especially 6 weeks old that is very young to leave she is probably calling for her mama, most breeders won't sell them that young unless they are mills mascarading as reputable breeders. There ARE exceptions, of course, and she MAY be fine at that age, but just keep your eye out for issues. You might want to look into getting her a cage buddy... preferably another joey, but a little older this time? I would recommend finding a breeder who waits till they are at LEAST 8 weeks, but maybe 10. (My girls were 8... my Heber was a rescue so he was something, like, 5 years. hee hee!)