Not sure if Bug

So i was Laning against an Akali, as Annie and i took Ignite to have her revealed in her Shroud thing. and it was going well untill i noticed as i ignited her and she went into it. She wasnt showing up, and when i went in after her using my W to try and kill her , it showed her up like at least 2 to 3 inches out side of her circle of Stealth heading to Tower, and healing up and i couldnt catch her from the suddeness of her not being where she was suppose to be, being able to Get away and such, and this happened a few times over the course of the Game. wasnt sure if it was a bug or not, But please look into it?