How to handle annoying pregnancy questions

Monica • My husband and I are 36 and 35, high school sweethearts, married in 2005, son Gavin born 11-27-15. PSU grad, work for small newspaper as a reporter.
I'm only nine weeks and I'm already getting stupid questions, like my co-worker asking to see my belly. There's nothing to see, and I could tell she knew that when I told her as much.
I've shared my pregnancy news with immediate family, a few close friends, and my co-workers, since I only have four co-workers and have been very exhausted so far. I fear more stupid questions as the months go on. Any advice? So far it's been this same co-worker who's being too nosy, but I'm sure she won't be the only one.
I also had to tell her a few months ago that we weren't telling anyone we're TTC because she would randomly ask, and she seemed slightly offended that I didn't share my pregnancy news at work sooner. I think part of her reactions are related to the fact that she's the only person who can fill in for me when I'm absent, and she already doesn't pull her weight.