In Chicago you can get off I290 and Parallel the interstate. There are times when I have gotten off the express way and the GPS thinks it is still on the expressway 50 feet to my right. It keeps telling me to get off at the next exit. Could be the GPS may have been confused on your location if it was a over/under situation

__________________
2012 X5 50i ZAP(2VA, 336, 465), ZTP, ZPP, ZPS(6VC), ZCW, ZRC, 322, 4UB, 4NC, 610
2011 ///M3 Silverstone II
2011 X5 50i(lemon)
-- SOLD --
08 550 Msport
07 X5 4.8I sport
04 545i sport
02 4.4i sport
01 540I M/sport
00 SL500
97 SL500