John Coleman felt his side deserved a point after Seamus Conneely's injury-time leveller.
A mistake gifted Tom Elliott Cambridge's opener before Piero Mingoia levelled in the 39th minute.
A deflected Ryan Bird shot gave the Us the lead 11 minutes from time before Conneely rescued a point.
"I think we deserved a point," said Coleman. "We played quite well and we controlled the game for periods but had a couple of spells where we let them wrestle control and we were nearly punished.
"I think we can create our own Christmas video of goals and gaffes as their first was another in a long line of goals we have given away. It's ridiculous.
"Their second was a wicked deflection but, for us, Piero's was a great finish and he was the person you wanted it to fall to in those situations as he is so composed.
"Then Seamus's is a real poacher's goal. He deserved that as he was my Man of the Match."