Eating very little, losing weight

Maya doesnt seem to be doing so good. She's been on medicine for high white blood cells (she has an infection somewhere) and it should have helped by now. The thing is, she is losing weight...this morning she was 67 grams...down from 77 over a week ago. She only wants to eat seed but even that, she doesnt eat much. She picks the seeds she wants and in the end, doesnt end up eating that much. I dont know what to do. She gets mad when I try to hand feed her with a syringe, she wont eat pellets...Even if she was eating seed and gaining weight, I would accept that but she is not gaining anything. Anyone have ideas on how I can make her eat more??
thanks.