If she was simply lifting her arms, as we do in the 3 pt. signal, I would probably ignore it as you did. You might say something to her when you get a chance about sportsmanship...how some might interpret her actions as un-sporting.
Having said that, if you have a player pumping his/her fists in the air, waving them, and looking at the crowd while doing so...you may have something all together different. That could be construed as inciting the crowd and/or self promotion...something we frown on in the H.S. game.
At least that is what I have been told by Veteran Officials.
RD