Hi, I'm Jina! The nuance is different. I would say 아니요 is "No", 아니라고 is "I said No" ex) 이거 맞아요? (Is this right?) 아니요. (No.) 뭐라고요? (What?) 아니라고. (I said No.) I'm sorry that I can't help you in Spanish, but I hope it will help you (: