My ten week old puppy was fine two weeks ago when I brought her home, but for the past few days she has been extra needy and whiney. Is this normal puppy behavior? It seems like a stage. How do I deal with it? She also is sniffing EVERYTHING and runnning around like a mad puppy. She is healthy, and I think its just her personality, but I wanted to be sure.

She is a puppy and like you said it's probably just a stage. She's at that point now where she knows you and is comfortable with your house, what better thing to do than explore and sniff stuff! She has probabaly become attached to you because you are her new mother and as she's still a pup and new so you've propbably spent most of the last two weeks with her so now she wants to be near you all the time.
To stop the needyness you can try ignoring her when she wines. Like if you put her in her crate and she wines don't coddle her right away, she'll get sick of wining eventually and then be quiet. Or if you're doing something and she wants you're attention don't give in and pet her perhaps say something like "go lie down" and continue what you're doing... again she'll tire of wining eventually.
If you're still worried you might try seeing a vet or asking when you go in for her next round of shots.
Good luck with the pup!