Morning sickness, low cal snacks

Hi all! I'm about 9 weeks pregnant and struggling with morning sickness. I haven't actually been sick but feel ill unless I'm eating or just after I've eaten. Obviously I don't want to put on any unnecessary weight so have been trying to eat little and often, mostly carbs as they seen to help the sickness the most but having raw veg and fruit as well, and still exercising but not as much as I had been doing.
Any tips on some really low calorie snacks or drinks that might help. I'm in the uk, thanks in advance x