Cranky and annoyed

After a day trip to San Francisco from New York for work and no sleep for two nights due to  babies that seem to regressing on the night sleep thing I am a little cranky today.
Not helped by the fact that I just answered the phone and it was for our nanny. Giving my phone number out to family I understand but this was a call from what a bank or something (they said it was an "urgent matter"). I am so annoyed. Why do people always have to take the piss. I am very good employer. I make every effort to be respectful -  financially, socially and personally. I made it clear that this is more than a baby sitting gig and it reimbursed accordingly. I clearly need to cool off before speaking with her.

How best to approach this? What would you do?