Sometimes a follower sits or stands with friends. It may be hard to tell who the cabeceo was for. It's tempting to try to clarify by some form of "who me?" However this is usually a wasted effort.
Imagine the following scenario.... three followers in a group .... a cabeceo comes from across the room ... it's not clear who the cabeceo was intended for ... all three followers point to themselves and mouth the words "who me?". The leader smiles and nods his head up and down. Now what? All three followers may firmly believe that they are about to have a magical tanda with their dream partner, but two of them are in for a surprise. This can be especially awkward if all three followers stand up and start walking toward the leader.
[Note: The same scenario can occur even if no one is next to you. Imagine another follower 5-10 feet behind you.]
Instead of "who me?" just do these four simple things: smile, nod, maintain eye contact and wait. If the leader approaches you directly, all is well. You get to dance that tanda with him.
If the leader approaches one of the other followers in your group, all is not lost. The leader has almost certainly noticed your smile, and nod, even though he did not approach you for the current tanda. You just added yourself to his mental dance card.
Bottom line: Don't use "who me?" as a response to a cabeceo. A better response is to either accept the cabeceo with a smile and a nod, or reject the cabeceo by looking away.
Please feel free to share your experiences and insights on this topic.