8 weeks loosing weight

I'm 8 weeks pregnant and this is my 8th pregnancy.. I have 3 girls, I have Lupus and hypothyroidism so its hard on my body when I'm pregnant.. Anyway I've lost 15 pounds so far, I'm not trying to. I take my vitamins drink water, I can't eat that much or I get sick..I know that some loss is normal in the first trimester but 15 may be over doing it.. Anyone else have this problem? Thank you.. You can see I'm starting to show already you'd was last week