cold have been worse

friday nite went to a car show in media pa. when i was ready to leave i put the car in gear and herd what sounded like play in the rear , drove off , started down rout 1 ,and herd what sounded like the spider gears braking. pulled off the road , pulled on the tires and looked under the car and didnt see anything wrong. put the car in reverse and it made a big bang sound but then stopped, put in forward and another noise and stopped, i proceded to drive back out on the highway, when all hell broke loose , i herd the driveshaft hit the floor pan,pulled off the road [ keep in mind this is about 9:00 in the evening] i got my flash lite out and looked under the car,there was no drive shaft looking harder it was still in the trans and had gotten wedged between the floor and tork arm.,both staps and bolts were still in the yoke and one cap the other one was gone , after 140.00 tow bill igot the car back home, purchased a new u joint and put the caps on it. what i noticed that theres no little tangs on the yoke to hold the drive shaft center. what had happened is i had someone install the new u joints in the drive shaft and he gave me these to snap rings ,and told me i may need them, i threw them away because i new the drive shaft had the same u joints front and rear and the two clips were if the joint went in the front....what a dumb ass... i figured it out when i put the new cups on the clips are internal and keep the drive shaft from walking....so glad nothing serious happened and no one got killed from my stupidity i can thnkof all kind of shit.. including the street rods that went pass me at about 70 mph ... thank God that drive shaft didnt come out. im embarresed to even tell you people about this but maybe my stupidity can save some one else