MY TRANSMISSION IS GETTING HOT WHEN I USED THE E-BRAKE? Why is this??????

if it happened right after the use of the e brake i would suspect the e brake is hanging up causing a drag hence the added load making trans. run hotter. jack the rear up and see if you can spin the rear tires you may want to apply e brake again try it then release it and try it again. if the cables are hanging up you may be able to work housings around and try to pull slack back see if wheel frees up?