There is actually a bit of history behind that.Slobodan Milosevic,during one of his political rallies in 90s,after public chanted "We love you!We love you!",said "I love you to".
But the way he said was so pathetic looking,and his infamous reputation afterwards stigmatized that phrase,so ever since then Serbian celebrities mosly tend to avoid to say "I love you too" after "We love you" chants.
I did not watch the ceremony,butif I were to guess,I think Nole did it with his tongue in cheek.
Btw,BigJane permabanned?Thank god for that.One of the biggest clowns around,and that really says something.
Thanks for the background on that.