Where you write “an ambulance is on it’s way,” you don’t need the apostrophe in “its.”
I almost feel bad for the operator, after Jeremy’s verbal assault. But they probably get calls like that all the time.

His tirade sounds entirely plausible. Well done in making it believable.

I’m still loving the way the dialogue is so powerful that you almost want to laugh to shield yourself from the emotional connection to what’s really behind it. Well constructed tension, so far here.