Losing too much weight?

Gwen
Hi ladies I know this is an odd thing to complain about, but I can't seem to keep my weight up. I eat all the time. I weighed 120 prepregnancy struggled to gain 25 pounds during my pregnancy and now my son is 18 weeks old ebf and I'm down to 112. The past couple of weeks I tried to eat more rich foods. More meat, pasta, high calorie beverages. And I still lost weight. I'm worried it'll start to effect my milk supply. Anyone in the same boat? What did you do about it?