blinking overdrive lamp

I was doing a short drive, around half an hour both ways, while I was going to my destination, my check engine light came on, then on my way back from my destination the OD light started blinking, at that time, I could smell something burning, I wasn't going over 65 mph, and I wasn't having any...

My overdrive light starts flashing after some miles on the highway. I cant notice any significant errors in the trannys function. It changes gears correctly according to me, and when lamp goes on driving on the highway i cant really detect an increase in revs. Tranny sounds and works fine as far...