With solids, it takes awhile for babies to learn how to communicate that they're full. They're often too busy enjoying the new tastes and textures. As long as you're sure she's nursing as well as she should, don't worry...some babies are just hungrier than others!
For the biting, try not to yelp or scare your DD when it happens. I used to calmly break the latch, count to 5, then put Tyler back on again without saying a word. He eventually got the message that biting interrupts his meal. If that doesn't work, take a look at the breastfeeding forum...biting is a pretty common problem, and there are lots of good ideas on there!