Andrea Pirlo had given the Rossoneri the lead, but Julio Cruz and Esteban Cambiasso - with the aid of a Nelson Dida howler - overturned the result.
Ancelotti said: "It was a very balanced encounter that was decided by some individual incidents.
He added: "Inter played a more physical game, as they have the characteristics to do that. We are certainly struggling more in Serie A than in other competitions and I hope from January to start a new training regime to fix everything, including having all four strikers back in action."
Ancelotti also complained about the referee after Cambiasso's rather clumsy challenge on Kaka.
"There was definitely a penalty on Kaka and in the second half we created many scoring opportunities. Admittedly, we did our part with a lot of mistakes, especially on Cambiasso's shot that did not seem irresistible."
Inter coach Roberto Mancini insisted: "We only struggled a little in the final stages of the second half, but controlled the game and deservedly won.
"In the first half they did very little to take the lead, as Andrea Pirlo made the difference with that free kick."
The Nerazzurri fought back with Cruz and Cambiasso to turn the match in their favour.
"Zlatan Ibrahimovic may not be 100 per cent fit, but when he has the ball he is always fearsome. Cambiasso is in good shape physically and in an exceptional period of form.
"In these opening five months of the season you could safely say everyone in the team has been great and contributed to our success."