Midget, I went through a phase of tangfastics.... I find that I get the same sharp/sweet sensation from manderins and pineapple. 
I had ms to about 20 weeks, and I got into the habit of comfort eating because it wasn't staying down, I was losing weight and needed to feel better. The problem is that those habits lingered after I stopped being so sick!
At 34 weeks, I'm just a few pounds above my weight at booking in, but about 12lbs heavier than I was at my lowest morning sickness weight. For full disclosure I started this pregnancy about 6 stone overweight, so I need to try and keep my weight gain down whilst making sure that I'm eating healthily to grow my baby. Women of an average/low weight need to gain more during pregnancy, I already have plenty of fat reserves!
What we must remember about weighing oneself during pregnancy
The number on the scales represents:
Pre-pregnancy: Your body
During pregnancy: Your body + your baby's growing body + enlarged uterus + extra blood + increased breast tissue + placenta + amniotic fluid + extra fluid + essential fat reserves for pregnancy and breastfeeding
Obviously having sweet cravings isn't just a concern from the point of view of weight gain though, and I agree that its good to try and keep our blood sugars under control.
Try having healthy snacks like fruit, yogurt, etc to hand when you feel peckish. If you have to have cake/cereal bars/jelly/similar then make sure you decide which options to go for based on which ones have low sugar and overall calories, rather than those labelled 'low fat' which have extra sugar in them to make up the taste.