Look, I'm not a little person and I've noticed students eyeballing the extra baggage around my midsection. There is no way in hell I'm showing at less than 6 weeks. It's bloat. It will be bloat until after your first trimester, most likely. Your uterus is still behind everything, and it hasn't grown enough to cause any changes like giving you a bump yet. You know what's even harder to hide? The already ginormous boobs. I was a 36DD-38D or so to begin with and I'm starting to spill over. Explain that one to people.
Some fun facts about pregnancy bloat:
It's not necessarily what you eat, though cutting back on salt can help
It's caused by hormones. You want those hormones, and so, you'll have the bloat.
According to the ladies who are further along, it can and most likely will go away, and will be replaced by the bump everyone evidently wants.
In the meantime, don't wear form-fitting clothes and deflect the questions that people shouldn't even be asking you in the first place.