There's no option for international shipping. I select "Add second shipping service" and they're all for Canada.
Are you using the stupid and poorly designed Simplified Sell Your Item form?
At the top right of that form is a link that will lead you to the Advanced/Business form.
It is both clearer and gives more options than the overSimplified form.
Offer Additional Service will show in both Domestic and International shipping.
There is good reason not to ship internationally at first until you get used to selling. Shipping is a particularly hard thing to learn.
Try starting a brand new listing. And look at the top right of the form for the word Customize.
I'm reluctant to experiment much with it, but it seems to allow the seller to Block international sales. Perhaps it is turned on to Block and you want to check it so that you CAN have international sales. At least to the USA.