how to hide I'm pregnant when I constantly snack?!

To keep the nausea away I feel like I need to eat every hour!! I work with patients at a clinic so it's hard to find the time in between them. But then I also don't want to start puking. I feel like at some point my co workers are going to get annoyed at my constant pretzel munching... any advice?! I'm also worried my boss and Coworkers are going to be angry when then find out I'm pregnant since I just started working there..