Apologies for not seeing your post for a few days. I wouldn't be surprised to hear from you that this behavior has already started to shift. It does feel instinctively like a growth spurt from what you say here. It really isn't possible to "overfeed" in the way you can do with a bottle. She may very well be comfort nursing, but that isn't problematic for her in any way... and it doesn't sound like it is driving you too crazy apart from being worried about it (there is an article on the site about comfort nursing as well). Nursing is as much about the bonding and instinctive need of a baby to suckle (especially in these early weeks) which serves to naturally increase supply as the baby grows, as it is about traditional notions of needed calories and nutrition.
The fact that the baby nurses so frequently and that you are so aware of small fluctuations in her behavior tells me that you are doing a great job being really tuned into your baby and her signals. Trust that you are not doing anything wrong or that changes in patterns like this one indicate a problem. If babies STOP nursing or become disinterested or lethargic, THAT is a pattern to be alert to... periods of temporary increases in fussiness or increased nursing generally signal growth or developmental changes in the baby or the breast and unless the change doesn't pass or seems to indicate something more than general fussiness or irritability.
My sense is that you know your baby well, so trust your instincts, but know that the only "pattern" I have ever seen in my girls is that just when you seem to settle into a pattern, it changes! In the early years, every few weeks, and then eventually every few months, you look back and realize they are a while different child!
Enjoy... feel free to write again and let me know how it is going. You can also find me on facebook at BellaOnline Breastfeeding Facebook Page