I don't think you look pregnant in this top, but I do think it may simply be too long for you - or at least, too long to wear over a skirt. How does it work over clamdiggers or skinny jeans? If I'm remembering correctly, you are petite, right? You may have better luck sticking only to petite empires. Proportions are key.
The color is lovely on you.
I would not give up on empire styles just yet - but do be very, very picky. I have a suspicion you can rock this look, with the right top. You want a band at the waist instead of gathers. Think of it like the equivalent of a full skirt versus an A-line skirt. You want more of an A-line to the bottom part of the top under the waist.
You have amazing collarbones, by the way!! I would love to see you in a sleeveless top. There is something about sleeveless + A-line/empire style that looks a lot better than the empire style with sleeves. I think the latter just adds to much volume all over, does that make sense? Whereas if you bare your arms then the volume below the waist looks more flirty. I could be wacked about this!
As for hiding the tummy, I like tops that have ruching on the sides, or can be scrunched up as if they were ruched. I also find anything with a pattern works great to fool the eye. And another favorite trick is to take a loose, shapeless top and put a cropped cardigan over it, buttoned at the waist, to create a waist. For summer you can make it a short-sleeve cardigan.
