Someone tell me I'm not overreacting!

I'm 5'1 and weighed about 130 after I had my first son 8 years ago. I lost weight so I managed to stay in the 120's and I felt good and healthy. I just had my 2nd son 2 1/2 weeks ago and I keep losing weight every day it's more and more. I'm not trying to on purpose and I'm starting to feel gross. I weigh 109 now. I've called the doctor and told them I don't have much of an appetite or when I eat my stomach hurts and I'm losing too much weight that I don't feel good but he just laughs at me and says most girls would be happy to be in my place. Should I look for help somewhere else?