By the book?

Bri
According to "when you're expecting twins triplets or quads" I should have gained 10 lbs by now. But I have actually lost two lbs since finding out I was pregnant. I am 10 weeks and 2 days and am eating small meals constantly. Trying to pick healthier choices but sometimes just too hungry to care. I am walking more and I haven't been able to eat any meat yet. But doing lots of dairy and beans. Any ideas?
I know it is normal for some women not to gain first trimester but I'm a little concerned cuz according to the book these first 20 lbs in this first 20 weeks is crucial.