Amanda Serrano‘s issues a mea culpa after accusation Katie Taylor from deliberately headbutting her repeatedly… going up to X to tell everyone that she was way out of step with her previous comments.

Here’s the deal… Amanda and Katie had an argument right before Jake Paul accepted Mike Tyson Friday night in Dallas – and during the fight, Katie’s forehead came up and hit Amanda right above her eye.

Taylor won the fight by unanimous decision… and Serrano and her trainer were not happy with the decision. Serrano told the interviewer after the match that it seemed intentional because Taylor does it in every fight.

However, it looks like Amanda realized she went too far by calling her opponent a dirty fighter… jumping on X and congratulating KT on her big win.