Flood scored all of the Red Rose's points as they stuttered to an unimpressive 18-11 win over the Italians, in a match where the away side scored the game's only try and dominated the second half.
The 27-year-old is disappointed that his side did not make the most of their early opportunities.
"It's a pretty quiet dressing room," said Flood. "There's a fair amount of disappointment. We just couldn't seem to get ourselves into the game after half-time, which was frustrating. We didn't have the ascendancy that we did have in the first half.
"We were pretty comfortable just before their try. We were in a good place, feeling we were about to kick on. We were really tested today, that 10 minutes after that try. We really had to be on our mettle and we did that and we managed to consolidate and make it right.
"It's disappointing not to have kicked on and not to have scored a couple of tries, because there certainly were the opportunities to. Had we managed to pick those up, we could've been in a position where we were able to have gone out there, express ourselves and kick on."
England face Wales in the title showdown on Saturday in Cardiff.