What would you do?

Uni B. • 💋 Mommy to a Princess 👑💛
Ever since I've been pregnant my coworkers have been making jokes about my belly & weight. They say things like..
•"That's gonna be a BIGG baby"
• "Ur getting big so fast"
• "How far long are u again?"
•"Go ahead and bend down (after dropping something), you need that excersice."
And my supervisor joins them!! The thing is she's like maybe 12 weeks pregnant herself and today she said I was having twins when another coworker asked me what I was having. 
I spoke to my supervisor after work and told her my displeasure in her comment and she got snark with me AGAIN. I told her how I don't feel it's okay, and that out of all people I feel she would understand and she said that she wouldn't be upset because she didn't mean it in a rude way, and she doesn't "wear her heart on her sleeve".
Mind you, I'm 17 years old, this is my first baby and I'm almost 27 weeks pregnant. This lady is almost 30 on her 3rd kid! It's getting to the point to where I don't even feel comfortable working here anymore!! But I feel I'm forced to stay because I need the money. 
I'm not sure if it's jealousy or what but I'm really upset. I don't understand how people can be so rude and inconsiderate of others! Am I over reacting? Should I just let it go? Is it just the hormones?