Oops

"Going up" John said as the light engulfed him and his whole body went numb. The numbness made it so that he couldn't feel the gun in his hand and didn't know he was still holding the trigger until he looked down and saw that he was. He let go right away but the damage was done. After a few seconds he was at Sarah's normal height, then his male height, then 7 feet, 8 feet, he eventually had to sit before he stopped growing at what he estimated was 15 feet tall. The room was pretty cramped for him now and as he tried to move he heard a smash and saw the chair he had shrunken reduced to splinters. He suddenly heard a very small voice coming the floor, he had to strain to hear it.
"John, you idiot! Don't move, you nearly crushed me!" Sarah yelled up to him.
He was trying to not to move but he was just so uncomfortable in this sitting position. He shifted slightly and felt something small break with a small crack. Terrified that he crushed Sarah, he called her name. No answer came at first. He called again. Still no answer. On the third time he heard her voice in his head, even more angry than before.
"YOU FUCKING IDIOT! YOU SHRUNK ME EVEN MORE! I'M SMALLER THAN AN ANT NOW!"
"Sorry", John said only to hear Sarah's voice in his head again.
"Don't bother talking, I'm too small to hear you and you're too big to hear me. I wished for us to be able to communicate telepathically. Now don't move! And I mean it this time."
There was silence, then Sarah's voice came to him, "Ok, I wished myself onto your shoulder. Christ your huge, I can't even see the ground from up here. Now just do as I say or I swear you'll think I'm a freaking planet compared to how small I'll wish you."