I love X-Men but this didn't make me angry.
This is when shes young, before her powers truly manifest into something huge, which we see near the end of the movie. Xavier is probably out doing whatever, maybe tracking down Colossus or Nightcrawler or whomever at this time, and once her powers explode, the Professor is like "wtf?" before going to find her. Its before he has the Blackbird and before he has Cerebro so they are just out there trying to track down people based off stories they are hearing about them while traveling commercial air.
Or, at least, this is what I tell myself? I dunno, it just didn't bother me since she was so young.