So my bunny is an unknown breed but she’s a medium size, maybe like 5 or 6 pounds, not big but not small. I went off to college and when I came back my mother had been giving her the worst, unhealthiest pellets I had ever seen! She gained a decent amount of weight, her tummy almost looked like she was pregnant! So fast forward me giving her an appropriate weight loss diet and changing pellets, one weekend I’m home (friday) and she’s still a too fat but she’s only been on the diet a week or two. Then on Sunday I look at her and her tummy is GONE. There is no way she could’ve been pregnant she’s our only bun, plus no babies anywhere. She is running around playfully and eating and normal, nothing appears wrong on the outside. What happened? Should she go to the vet? I’m only asking first because as a college kid money is very tight and I only want to take her if I really need to.
P.S. it should be noted that when I was gone during the week my mother was giving her lots of kale and sometimes carrots (in copious amounts) even though I yelled at her several times not to do that! I can only tell her not to so much and I can’t do anything about it when I’m gone 
She also doesn’t run around outside because our backyard has glass in it, so I don’t think she could have picked up a bug??
Please help, I am super worried!!!!