There was a Britannic built at the same time?
Yes, pretty much. There were three sister ships, Olympic (1911), Titanic (1912) and Britannic (1915, keel laid 1911). Britannic ended up serving only as a hospital ship during WWI, and was sunk during one of her missions. Olympic had a long and successful career, making her last crossing in 1935, and was eventually scrapped.