The SPA means that your Pokémon was originally from Spain. Foreign Pokémon all have 3 letters that indicate the country (i.e. JPN from Japan, ENG from England, etc.)
This is actually a great thing for a few notable reasons. First of all, foreign Pokémon get 1.7x experience from battling (compared to 1.5x from a traded Pokémon from within your country), and not only that, you can use the Masuda method to get a shiny Eevee (which is very valuable).