Opening hands?

Courtney
So my 3 month old still keeps her hands in a fist most of the time? I thought at this point her hands would be open more, and she would be grabbing at things, and she does sometimes but not as much as I thought she would. Granted most of the time her fist is stuffed in her mouth as she's teething, but im just getting a little concerned she's behind on something she should be doing :/ 
An insight?