The youngster missed the 1-0 defeat to Irn-Bru First Division title challengers Partick Thistle in midweek after breaking down in training with an ankle knock.
Billy Reid's side face Livingston tomorrow afternoon aiming to pull away from the relegation zone.
But the Accies boss has attacking worries.
He said: "It is a blow for us and for the lad. It all came about pretty innocuously when he was playing head tennis with some team-mates.
"We have gone very quickly from having no injuries for the first time this season last Saturday to having Andy out and a major concern over Jon McShane, who picked up a knock against Thistle on Tuesday night."