One is the flag, which is totally wrong. The German flag you have is the post war one. The pre-war (before the Nazi regime) was a black white and red flag.
You are right and wrong. Between 1919 and 1933 the German flag was black, red and gold. But the flag of the merchant marine was indeed black, white and red with a small black, red and gold one in the upper left corner.
I think this one would bee the propper one shown.