It is possible that this small country only has one exit node. Or only one exit node with an exit policy that allows what you're doing. 

By choosing a country with only one exit, you restrict your possible exits to a set of only one, so every circuit you build will use this one exit.

If you go to the bottom of this page: https://torstatus.blutmagie.de/ you can:  

* Sort Router Listing By: Country code  
* Sort Order: Ascending
* Bad Exit, Hibernating: No
* Exit, Running, Valid: Yes
* Apply Options  

That will show you all good exits by country.