First of all, don't maintain a speed to "maintain his satisfaction." Maintain a speed appropriate for your mode of transport. By all means permit faster vehicles to pass you when it is safe to do so, but don't feel obliged to adjust your speed according to the expectations of others. (This is good advice for motorists as well as bicyclists.)

Second, did you signal that you were making a right turn? I got a feeling reading your post that you didn't signal your intentions, and so the motorist *reasonably* assumed you were positioning for a left hand turn.

If you failed to signal, you failed to correctly control the situation (oh, and you broke the law, too). If the lane is not wide enough to share with a motor vehicle, it is your responsibility to control the situation, by positioning yourself far enough to the middle that you cannot be passed, signaling your motions to the vehicle behind you, and to exemplify the courtesy you expect from others by sharing the lane when it is finally safe enough to do so.