The British driver, who agreed to join Mercedes from McLaren ahead of the new season, was speaking after the first day of testing in Jerez this afternoon.
"It was not too bad, it just felt like driving a different car," Hamilton told Sky Sports News. "I am not sure what else to say, there is a lot going on, a lot of new controls I am getting used to and so much information coming in and just trying to get on top of it.
"The steering settings that I had before are very different on this car and there are a lot more buttons as well. So utilising those and understanding the set-up changes that they make - the dif settings.
"All the calls are different. They use different terminology on top of that and the car brake bias has six settings instead of the three I used to have so there is a lot of different stuff going on."
The campaign will get underway in Melbourne on Sunday, March 17.