Kristin Cavallari Cries After Son Roughed Up In Tackle Football Game

Kristin Cavallari is an emotional wreck over her son's first foray into tackle football ... breaking down in tears as she admitted watching him get roughed up on the field is "one of the hardest things I've had to sit through."

Cavallari -- who shares her 6th grader, Camden , with ex-NFL quarterback Jay Cutler -- opened up about her struggles on her "Let's Be Honest" podcast ... explaining how her boy is old for his class, but outsized by his 7th and 8th grade opponents.

While KC said Camden's first two games went off without a hitch, the third was a different story ... and he was on the receiving end of some "really bad" hits and "went flying."

Cavallari explained her motherly instinct told her Camden was scared after the first time he was roughed up ... which "f***s me up even more."

"Thinking of him being scared out there just wrecks me," Cavallari said. "It just wrecks me -- more so than the physical aspect. Obviously, physically, I don't want him to get hurt. And then he got hit a couple other times."

"It's so hard seeing your baby get hit."

She even revealed she was in her feels prior to her son even taking the field for tackle football ... saying she cried the night before his first game.

Cavallari said she knows how great contact sports can be for kids ... but it doesn't make it any easier on her.