Poor battery life in a new MBP

I just bought a MacBook Pro, 15 inch 2017, 3.1 GHz Intel Core i7 processor, 16 GB 2133 MHz memory with 500 gigs of storage space. Mac OS 10.13.1.

I paid more for it than I did for my first car.

The specs say I can get up to 10 hours of battery time out of it. But the first day I used it without a power cord, it took 2 hours to burn through half the battery life. My 2013 MBP that this replaced takes an hour and a half to burn through 50% of the battery life.

Did I get a lemon?