
Quoting
flyingron
Are we talking about a NY lawyer? He most likely really doesn't know what is going on in PA (and really can't help you there, he's not authorized to practice).
Depending on just what is going on in PA there may or may not be a warrant. Did you miss a date there? Often, if they know where you are they'll just file the charging documents and the first thing you will get is a "Notice of preliminary hearing/preliminary arraignment." They just expect you to show. You miss that (at least without a lawyer in the PA county involved) there will certainly be a warrant. They'll typically do the arrest stuff (fingerprints/mugshots) at the time of the preliminary hearing (or they'll send you a separate letter telling you to come in for those).
If a warrant is issued, NY can certainly hold you until PA decides whether it's worth their while to come get you. Which county? You will be held until they come or NY decides they're not going to deal with waiting anymore. Once you get to PA, you've got 72 hours to be brought to the magistrate down there (though in most counties, they have one on duty 24/7, so you won't wait that long).
So fill in the blanks a little bit. Have you received the PA charges? If you have, you can most likely contact the court involved and make sure you have the appearance date you need (it often does change).