Glad you are OK...

I launch solo all the time like that....but I use a VERY long rope attached to the trailer winch...after the boat begins to slide off, I pull the truck up a little so I don't have to get my feet in the water....then pull the boat over to the side....

actually, I once slipped on the algae that was out of the water....another time I had a hard time getting the boat to slide off so I tried walking out on the trailer to push it off.....made the mistake of stepping on the carpeted runner.....the runner twisted sideways and dropped me all over the trailer in two feet of water....almost broke my leg....bruised my arms and ribs....you only make that mistake once....