George Boyd fired promotion-chasing Posh, who remain fourth, into a sixth-minute lead but the Us levelled 11 minutes later through Ian Henderson's looping effort.
"I don't think anyone could argue that we deserved any more than a point from the game," said Ferguson. "Sometimes you have to give credit to the way the other team plays and that's certainly the case this time.
"Colchester were an excellent team and showed their quality, especially in the first half when they penned us back and had us under all sorts of pressure.
"We changed our shape and system at half-time and I thought we were much better as a result. The lads kept going terrifically well right to the end of a third game in the space of a week, all of which have been played on heavy pitches.
"Our goalkeeper Joe Lewis in particular was impressive with a number of good saves, but the thing that disappointed me was seeing the game very stretched. It certainly got a bit too open for my liking, but there is no doubt it will have made very entertaining viewing and this could prove to be an important points for us come the end of the season."
Source: PA
Source: PA