A first-half incident in the Blues' 3-2 loss at St James' Park saw Coloccini's boot make contact with Ba's face as he went to head a rebounded shot in the box, but referee Howard Webb did not take action.
The Senegal international, returning to his former club Newcastle for the first time since joining Chelsea, received lengthy treatment on the touchline and returned to action briefly with a bandaged face before he was substituted for Fernando Torres.
Ahead of that swap, Newcastle scored the opening goal in the 41st minute as Jonas Gutierrez nodded home Davide Santos' cross.
Benitez confirmed the striker has a broken nose and believes the referee should have issued a sending off and a penalty for the incident.
He said: "We couldn't change the situation of Demba Ba. That was a penalty and a red card for me. It changed the game. We lost one player with a broken nose and used one substitution.
"After watching the replay it's very clear. A player with his nose broken and bleeding for five minutes is good evidence.
"I have a lot of respect for them (referees) but it is just the decision that is wrong.
"I want to remind you that that happened because sometimes you don't remember these things."
Asked how long Ba is likely to be sidelined, Benitez added: "I don't know. We'll have wait."
Chelsea came from behind in the second half through two superb goals from Frank Lampard and Juan Mata but were pegged back by Newcastle's new signing Moussa Sissoko, who added a stoppage-time strike to seal the win.
Benitez hailed the response of his side after the break, adding: "The reaction of the team in the second half was fantastic.
"We scored great goals, we had more chances and we made the mistake of allowing them to play counter-attack, which is something we will have to improve on."