TELEPORTED INTO THE FUTURE

I was in a picnic with my friends, in the hilly area. I saw a cave there and went inside to see how was the cave but suddenly I fell on the ground hitting an unsual looking stone and after that somehow i was teleported into the future ,and to my surprise I turned to a grandmother. I couldn't remember anything what happened in the cave.I didn't know if my parents were worried for me or not. I was 82 years old in the future and would die any time. So will I be able to return in the present world? But how?