i travelled to usa during 25th jan 2003 to 7th march 2003.while leaving at LA airoirt they did not remove the small white strip (5mmx100 mm long) stapled to my passport.is it the I-94 ?I entered India on 8th march 2003 and there is rubber stamp to that effect.do I have a cause for concern if I get visa second time and enter the usa airport?