please help Transmission
 

Some one please help,
I was driving my car the other day. Its a 88 mazda rx7 n/a. I was being pretty agressive with it. Now it seems it will not relese from 5th gear. Even at a compelet stop if feels as if it would not realese from 5th gear. I pulled the transmission, and it seems to shift perfectly fine, and i also pulled off the cluth. The cluth seems fine as well. I have no idea what it could be. I definitly smelled somthing burrning.
any ideas?