I think S.S. Means Steamer Ship or something, so it's british

The SS prefix stands for Steam Ship- it is not with respect to country.
QE-2 was built with steam turbines making her the SS QE-2.
She has since been converted to diesel, so I suppose technically she would be the MV Queen Elizabeth 2 now-
She was and remains the RMS QE-2.
The Olympic, Titanic, and Britannic were British flagged ships, but IMM was the holding company who owned White Star Line.
The majority share holder of IMM was J.P. Morgan, who was an American.
This is why the case is sometimes made that the ships were American owned.

well america payed for us to build the ships so they are not technically ours

America did not pay to build them. America had their own fleet of ships, why would they aid there competitor? An American was the majour share holder, that's why, people would invest in our ships because Britain was the nation with the best ships. Britain had the right to call on them because a British company built them, and owned them.

mmm you might have made something there,

Well its quite confuse.

"SS "stands for Screwdriven Steamship, whereas "RMS" stands for Royal Mail Ship or Royal Merchant Ship. A steamship would normally be referred to as "SS" unless it was under contract to carry mail, when it would use the prefix "RMS" ( Royal Mail Ship). Therefore Titanic is correctly referred to as "SS Titanic", and also "RMS Titanic" as she was carrying mail under the auspices of His Majesty's postal service. When not carrying mail, a ship would revert back to "SS".
All ships, military and civilian, that were under the British flag carried the distinction of "R.M.S." This, in effect, gave the ship the protection of the British Crown. An attack on an R.M.S. was considered an attack on the crown and an act of war.

I think the S.S. prefix is for all steamships whether screw or paddlewheel- the wreck of the S.S. Republic currently being salvaged was a paddlewheel ship but did carry the SS designation since she was steam driven.

Well why was it called ss to if she already had the RMS in her name.

In 1912 White star was owned by the american J.P.Morgan