Wren swallowed pennies (updated)

I arrived back from the supermarket to hear that was a little incident while I was gone. Apparently Wren was lying on the couch and he swallowed two pennies. Joshua has googled this and it is not terribly uncommon and the initial danger of choking and it lodging in the oesophagus seems to have passed.

Here is my interview with Wren:

Wren, what happened to the pennies?
I ate them and I swallowed them and I ate them and I cried about them. I ate one, two.
Why did you eat them?
I don't know.
Was it a mistake? Was it owie to eat the pennies?
No, it won't.
Where are they going?
They are going in my mouth and down my throat and in my tummy?
Where are they now?
They are IN MY BLOOD. (he rubs his legs)
Are they coming out your legs?
No, they are not. Look, there is no space there. No hole there. (showing soles of feet)
They will come out in your poop.
No, there is no hole there (rubbing bottom).
Yes, there is... they will come out in your poop.

I am waiting to speak to the on-call nurse.

Update:
The nurse asked a lot about his swallowing and asked me to check he could eat white bread (hamburger bun went down fine). Asked about pain. He seems fine now. The pennies need to pass in 3 days or we shall have to see the pediatrician semi-urgently (like 24 hours). I have to watch his poop for pennies and any sign of distress / blood. Also to watch for abdominal pain, abnormal lethargy or illness and recurrent vomiting.

For now, we are doing OK.