1998 Ford Contour Slipping and will not shift into OD

There is very rough shifting into 2nd gear. Very high rpm then after shift very low rpm. Transmission will not shift into OD and the dashboard OD ON/OFF indicator light begins blinking after only a few miles driving. Transmission slips when downshifting if I use too much fuel pedel force. I checked the fluid level (after 20 miles) and it was within the bottom 1/4 of the marks. There was darkening and a burnt smell. I have some rebuild experience with other engine components and have installed/removed both rear wheel and front wheel drive transmissions. I am confident enough that I would use a rebuild kit if the necessary speciality tools are reasonable to acquire.