The 21-year-old joined the Shrimpers from Brentford in January last year but is yet to make his first-team debut.
Club physio John Stannard told the club's official website: "Clark may have a small hernia. We took him for a scan on it last Thursday and we will know Tuesday if he will require an operation.
"It's only a small problem though and he would be off a couple of weeks."
Source: Team_Talk