1998 Ford Contour 98 Contour: Can't put into drive, but 2nd

This morning I turned my car on just fine. Put it into Drive and nothing happaned. Felt like it was in Neutral. Reved the engine.. nothing... Switched it to 2nd and off it went. Got going fast enough and switched it back to Drive and everything was good. Until I slowed down and bamn... same thing again... Back to 2nd... just to keep going. Help!?