Each person is different, but I had to get my body adapted to the change before I started having good workouts again.
After doing this for awhile, I have more endurance and better results on low carb. I also get a little more energy boost adding in coconut oil in my diet.
I'd just say to give it sometime for your body to adjust. Even if you go easy on workouts for a couple of weeks, I think you'll be better off in the long run. JMO