Help next to my cockatiel?

HELP! my cockatiel is getting nasty with me and i dont know why! She isn't ready to come out of her hold yet but sometimes when she wants food, i out some in my appendage and she eats off of it. But, when she doesnt want any more she gets harsh and hisses and bites me. i am trying to be calm but sometimes can't help to say something to her. I hold no clue what to do and am thinking that its just her personality. what do i do ?
Any free bird traning video?
Answers:    sounds like your bird requirements you to leave it alone sometimes. Let the bird come to you for attention instead of going to it all the time.
My 10 year weak cousin doesnt know...
Time and patience is the knob here. Get a good book on these birds and should find lots of tips. Do not do anything when she is nasty to you but reward her for doing nothing and human being good.
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