único, sólo, únicamente in this sentence?

Question

Oye, sólo estoy bromeando. o

Oye, estoy único {únicamente?} bromeando.

Sometimes it's the seemingly easy stuff that throws you. Also could someone explain the placement of "only".

Gracias

BTW the English is "Hey, I'm only joking."

Answer 1

único is "only" like "the only one".