Don't worry, Marisa. I flew into Newark when I visited NYC and yes, there were queues, but it was normal and very efficient. I'm from UK, so sameeal with EU passport. However, this was my final destination, not a changeover, so maybe it took longer. Bear this in mind - Newark is smaller than JFK or another airport you could have changed over on, so lines should be smaller.
Take Mariano's advice if the flight does get in a little late, and other than that just enjoy!
Have fun!!
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