When I was playing I've notice a little bit of something I would consider unfair. If you're battling a NPC pokemon, and you're pokemon fainted, you're allow to choose a new pokemon but choosing a new pokemon would allow the NPC to attack you two time in a round, I think this was weird but I figured it was just how it suppose to be but when the NPC pokemon faints, it's allow to attack my pokemon after picking a new pokemon? Even sometimes it even allows the NPC to play two moves in a row after picking a new pokemon. Is this how it suppose to be or a bug?

Moved to General Support - I think what you're looking at is that pokemon outspeeding yours, so therefore it seems it's attacking twice; If it's faster than the one you send out, it will attack before you get another attack in. Hope this helps!