[fatum]

That makes sense, referring to the person あなた almost sounds like you're being condescending. "Hey you there" is what I make out of it.

If this sentence logical or phrased correctly?
ば日本語がわかりますその後、大好きあります。
If you understand Japanese, then I love you.

I'm not sure if ば and その後 are in the right place. Google translator yields:
Then if you know Japanese, I love you.

as the translation.