Hi S.,
Way to go for loving your family enough to be a Stay-at-Home Dad. It's great to hear you love doing it.
It is quite typical for children Shayla's age to get frustrated when things don't go exactly as she wants. Loving her enough to teach her how to deal with these emotions can be a challenge.
When she gets upset, she is not ready to talk at length about what's got her upset. A good approach to try is to "extinguish" it by paying her as little attention as possible. Tell her you can't understand her when she talks in a whiny or even screaming tone. If she is old enough to be sent somewhere to calm down, do it. If not, make sure she is safe and leave her to deal with it. Tell her you'll be happy to do whatever (talk or play or let her get her milk, etc.) once she is ready to use her Big Girl Voice and Manners.
She'll figure out real fast that this type of behavior does not get her anything. Once she has calmed down, you can then talk about other things she can do the next time she gets upset - help her brainstorm and choose something to try.
Acknowledge all the progress she makes - no matter how little each time. This will help her (and you) recognize that she is growing up and getting better at handling frustrating situations.
With your loving guidance and that of your wife, you can help your daughter get through this stage.
Good luck!
Parent Coach J. B