Bell, 24, received immediate ice treatment and was then taken to a nearby hospital for precautionary scans after being struck in the nets by paceman James Anderson.
Bell, who scored a century in England's last warm-up match against South Australia, was expected to be promoted up the order to bat at number three after opener Marcus Trescothick returned home last week.
If Bell was ruled out, England would be forced to reshuffle their batting line-up again.
The most likely replacement would be uncapped Ed Joyce, who was added to the squad as a replacement for Trescothick.
Michael Vaughan arrived in Brisbane yesterday afternoon but is not expected to be fit until the third test while he continues his recovery from knee surgery.