same a little over 2 weeks for my boy, now i only feed him hikari betta bio gold.it took my boy perry about 2 weeks before he started eating (now he goes crazy for food). Sometimes bettas will eat right away and sometimes they need to adjust to their homes. Just give her food every day. I suggest high quality pellets like Omega One or New Life Spectrum (if money is a concern, Omega One pellets are actually the same price as any of lesser quality pellets). Just drop a pellet in and if she doesn't eat it, then remove it. Keep doing this every day, eventually she'll figure out she's supposed to eat it. Then she'll figure out that you are "the giver of food" and she'll always be happy to see you.