There are a couple of identifiers to a load-bearing internal wall:
- If there is more brickwork above the wall, it is probably a load-bearing wall
- If the floor joists are running perpendicular to the potential load bearing wall, it is probably a load bearing wall.
However, there is only one way to guarantee that you will not be wrong about the status of a wall. It is to appoint a structural engineer to give you the answer.