The 19-year-old winger was forced off in the second-half of Tuesday night's 5-3 Capital One Cup victory over Notts County at Villa Park after taking a knock to his ankle.
The 19-year-old winger saw his first start for the club cut cruelly short on the hour by a heavy challenge on his ankle and Sherwood later admitted that he did not know how long his latest summer signing would be out for.
“The negative is that Adama got injured,” he told the club’s official website. “He's a real talent. It was his ankle. He took a heavy knock - I thought it was a bad tackle.
“It doesn't looked good to be honest. It's too soon to tell how serious but he's packed in ice and hobbling around.
“The only way to stop him at the minute is to kick him. He's a marked man. He will have to get used to it.”
After an eye-catching debut display off the bench in Saturday’s 2-1 loss at Crystal Palace, Adama was brought into the line-up for Notts’ visit as one of nine changes from the weekend and proceeded to showcase the talent that prompted Sherwood to hand Barcelona £7 million for his signature earlier this month.
As well as dominating with his pace and dribbling skills down the right flank during his 60-minute outing, the ex-Barca hotshot marked his home bow with his first goal for the club thanks to Jack Grealish, who set up his fellow teenager’s 24th-minute equaliser to cancel out Genaro Snijders' earlier opener.
Villa were forced to haul themselves level twice more on the night before settling the tie in extra-time through Scott Sinclair’s third goal and a Joe Bennett strike, but Sherwood stressed that his side would not be so open when it comes to Premier League action.
He added: “I got cramp watching it! When you pick a side with Carles Gil, Jack Grealish and Jordan Veretout in it, I think you're going to be open. We knew that.
“But to be quite honest, we wouldn't be that open in a Premier League game. We would balance off the squad a lot more.
“But the reason those players were picked was because they needed the minutes on the pitch. They probably got a few more minutes than I would have liked in the end.”
With Saturday’s Premier League visitors Sunderland also enjoying a dramatic 6-3 cup win over Exeter City, the coming match could well be another high-scoring affair – albeit one in which the hosts might have to do without their new teenage sensation.