Following an early afternoon shoot around Wednesday in Indianapolis, Stephenson said he and Paul George both said things they shouldn't have.
Miami leads the Eastern Conference finals 3-1 and can wrap up the series Wednesday night in Indy.
NBA officials fined George $25,000 for criticizing the officiating in Game 4. George said he expected the fine after complaining about ''home cooking'' and saying Indiana ''outplayed'' Miami everywhere except the free throw line in Monday's 102-90 loss.
But Stephenson faced the most scrutiny after suggesting, prior to Game 4, that LeBron James' trash talk on the floor was a ''sign of weakness.''
Stephenson said he should have kept his thoughts private, and he called it a learning experience.