The 22-year-old seemed to pull up with a muscle problem in the first half, with Fabian Delph getting ready to come on, but Alli managed to continue until being taken off after 80 minutes.
The Tottenham Hotspur player had a scan on Wednesday (AEST) while his teammates trained after picking up the strain in Volgograd.
"We had to keep monitoring Dele," England manager Gareth Southgate said.
"He was feeling a little bit of an issue just before half-time, but he felt he could carry on."
England play their second match on Sunday in Nizhny Novgorod against Panama, who lost 3-0 to Belgium in their opener.
Depending on Alli's recovery, Southgate may opt to rest his creative midfielder in favour of Ruben Loftus-Cheek, who looked lively in the closing stages against Tunisia.