Instead of pointing to the spot, referee Robert Madley booked Carles Gil for diving and awarded a free kick to the visitors when the Villa substitute went down under a challenge from Younes Kaboul.
Sherwood was furious on the touchline and went to take his frustration out on a cluster of water bottles, but refrained from actually doing so.
The score was 2-2 at the time and, with just 10 minutes remaining, a penalty would have presented Villa with the chance to turn their dominance into three points.
In the end Sherwood's side had to settle for just one and he said: "I still think it's a penalty.
"Otherwise he rolls it into the net
Why else would he go down.
"He is clean through and I've asked Gilly if there was contact - he said there was.
"I think Younes pulled out actually but if there is contact you're entitled to go to ground.
"We would have grabbed the goal we deserved."
Scott Sinclair followed up his midweek hat trick in the Capital One Cup with another two goals, his first from the penalty spot.
Either side of Sinclair's first-half double, Yann M'Vila's free kick put Sunderland ahead and Jeremain Lens netted the Black Cats' equaliser shortly after half time.
Sherwood said: "Despite being disappointed at not winning, I was pleased with how we played.
"We lost a lot of goals at this club from Christian Benteke
He's obviously moved on and we need to find them from different areas and I think we created chances from all areas of the field.
"We had 22 shots at goal, or whatever it was
Their keeper saved well and we should have had a penalty.
"It was all hands to the pump for them but at the end of the day we walk away with less than we deserve, so you give them some credit.
"I can be disappointed we didn't win but I am encouraged to see that what we are working on in training is starting to show."
Meanwhile, Sunderland boss Dick Advocaat backed Lee Cattermole after the midfielder conceded a second penalty in four Barclays Premier League matches.
Cattermole, substituted at half time at Villa Park, clumsily climbed over the back of Sinclair, giving the Villa forward the opportunity to equalise from the spot.
It brought back memories of the opening day defeat at Leicester when Cattermole was replaced after giving away a spot-kick with a rash challenge.
But Advocaat said: "There was no need for that kind of penalty but I will never say anything bad about Lee Cattermole because last season he did brilliant for the team.
"But mistakes like that are no good."
Source : PA
Source: PA