Halle Berry -- WHAT Concussion? Returns to Filming

Halle had no visible injuries or bandages as she walked to her trailer on the LA set of "The Hive" -- her first day back at work since she was rushed to a hospital on Tuesday night.

As TMZ reported, Halle fell and hit her head while shooting a fight scene -- and people on set were concerned because she started throwing up after the fall ... a common sign of a concussion.