Increased hunger problems!

I am 22 weeks & 1 day pregnant, yes I know pregnancy causes increased hunger (duh! you have little someone extra special to feed) but I'm a little confused, I will eat something then literally 5 minutes later be "stomach growling" hungry. This happens everyday. I am scared of eating too much and gain too much weight. I don't want my doctor/ midwife giving me a disappointing look at my next appointment, or even find out I have gestational diabetes. Though everyone keeps saying "FEED THAT BABYYYYYY ". Don't know when enough is enough or to much due to the extreme increased hunger im having. Hope im not the only one with this issue :(