Weight loss while breastfeeding

So I'm a little bit concerned.... I had my daughter last September so just over a year ago. When I had her I had gone down to around 140lbs. Well now into this November I've lost a total of around 25lbs within this time frame. I'm now 115lbs and I have 2 kids... I haven't been 115lbs since before my husband and I were dating. I still breastfeed my daughter to sleep but she's on foods for every meal. Is this something i should be concerned about.... or is it fairly common to just keep losing weight when you're still nursing? I eat normally like any other human lol