What happens in the immediate aftermath of the assassination:
CINNA
Liberty! Freedom! Tyranny is dead! Run hence, proclaim, cry it about the streets.
CASSIUS
Some to the common pulpits, and cry out 'Liberty, freedom, and enfranchisement!'
BRUTUS
People and senators, be not affrighted; Fly not; stand stiff: ambition's debt is paid.
CASCA
Go to the pulpit, Brutus.
DECIUS BRUTUS.
And Cassius too.
BRUTUS
Where's Publius?
CINNA
Here, quite confounded with this mutiny.
METELLUS CIMBER
Stand fast together, lest some friend of Caesar's Should chance—
BRUTUS
Talk not of standing. Publius, good cheer; There is no harm intended to your person, Nor to no Roman else: so tell them, Publius.
CASSIUS
And leave us, Publius; lest that the people, Rushing on us, should do your age some mischief.
BRUTUS
Do so: and let no man abide this deed, But we the doers.
Re-enter TREBONIUS
CASSIUS
Where is Antony?
TREBONIUS
Fled to his house amazed: Men, wives and children stare, cry out and run As it were doomsday.
We see that Antony has fled immediately; he left to go home probably fearing that he would be next – because that’s what he would do. So while Antony makes preparations we get the following scene.