Baby cries for anyone but me

My baby is almost 12 weeks and she seems to cry for anyone but me now. Even when my husband holds her, she gets fussy. I've been home with her 24/7 pretty much since she was born. I can't tell if it's just that I know how to calm her best or if she's having legitimate separation anxiety. It's hard on my husband because he can barely hold her without her crying. And I go back to work soon and she'll be home with him part time and in daycare part time. I'm afraid she'll just scream and cry the whole time. Did anyone else experience this? How can I at least get her used to her dad taking care of her?