No appetite :(

Anyone have a complete loss of appetite in the first trimester? I get nauseated if I don't eat, but then when I do, I can barely eat more than a few bites. And then I'm nauseated afterwards! I'll get cravings for cookies or another food, but by the time my fiancé brings them home, i don't want them anymore. My dr says to just eat nutritious food every few hours, but I don't feel like I'm eating enough for the baby. Any advice?