The on-loan Celtic striker, 20, made his first start for the Pilgrims in the 3-1 loss at home on Tuesday night but was forced off through injury after just 25 minutes.
The Republic of Ireland Under-21 international joins Bradley Wright-Phillips on the sidelines, and Sturrock said: "Bradley Wright-Phillips was a blow and Sheridan was a blow.
"He [Sheridan] has got a haematoma in his thigh, so he's going to struggle for a couple of weeks."
Source: Team_Talk