From passion to pain: TLC to premiere 'Sex Sent me to ER'

Gregg is horrified after Jen's head goes through the wall during his first sexual experience on TLC's "Sex Sent me to the ER" (TLC)

The first time Gregg Casarona ever had sex, the walls didn’t just shake — they shattered.

The 440-pound project manager was 21 at the time and had been dating his girlfriend Jen Gerakaris for about a month when they decided to take things to the next level.

Welcome to the new TLC series “Sex Sent Me to the ER,” premiering Dec. 28.

When things began to heat up, Casarona thrust the 110-pound Gerakaris backwards with all 440 pounds of his girth. And Gerakaris’s head went right through the basement’s sheet-rock wall.

“My initial reaction was, ‘I killed her,’ ”Casarona told the New York Post. “‘This is my first time. And Jen is dead.’ ”

After a couple of terrifying seconds, Gerakaris slowly pulled her head out of the wall and looked at Casarona incredulously.

“Why’d you stop?” she asked.

“He looked like he was about to have a heart attack,” she says. “So I just wanted to lighten the mood.”

But Gregg was shaken and insisted on taking his lover, who started to become dizzy and nauseous, to the hospital. She was diagnosed with a concussion.

Their story will be featured — with a PG-13-rated reenactment — in the premiere episode of “Sex Sent me to the ER.”

Click here for more on the show from The Post.