1992 civic ex auto

went to phoenix, drove home last night back to vegas i hear a boom like a belt broke, battery light came on. i was pretty close to home car went into limp mode gauges stopped working lights stopped working. i get home i come to see that the tensioner bolt fell out and the belt was not spinning the altenator. i charge the battery and fix the alt issue. put it into drive and hear and instant grind and clunk and now the car doesnt move in drive or go in reverse. this car is an auto. the transmission sounds like its trying to catch a gear or something....

the car has 177k miles on it just changed the trans fluid about 800 miles ago. is the trans out or did my altenator issue screw something up with my auto tranny that caused it to go out if that is the case