Honda problem

Hi,
7 weeks ago I purchased new Honda City Vti-L manual and I had no problems with it at all. However in the last 10 days I have noticed that sometimes when I start the car first thing in the morning it sounds like its struggling a bit (hard to explain, it just sounds different). I wasn't too worried about especially since its not there always. However, I have also noticed when I drive in the 4th gear, and try to keep it at steady 60 km/hr it feels like its slightly jerky. Or jolting. It almost feels as its braking or choking. I am wondering if this is normal or if I should I be worried?
Thanks