HI LisaM ,
My doc says that all the time too and also that the change of seasons do it too!! I found a web site that tracks or tells you what the Barometric pressure is in my area, i think you can hit the link at the top of the page and change the zip code to get yours. Hope this helps.
http://www.wx.com/myweather.cfm?ZIP=13790
Hope you feel better,
Amber