Slams Tua For Returning To Game

Tua Tagovailoa was foolish for returning to the Bills game on Sunday after slamming his head on the turf ... so says famed neuropathologist Bennet Omalu -- who tells TMZ Sports the Dolphins quarterback put his life at risk by making the comeback.

Dr. Omalu -- who's the real-life inspiration for the famous Will Smith "Concussion" movie -- says that under no circumstances should Tagovailoa have come back into the contest in Miami after he was initially knocked out of it.

Omalu says he suspects Tagovailoa suffered a concussion based on everything he saw on the game's broadcast ... and he said the 24-year-old should have protected himself and his future and stayed on the sideline the rest of the…