It's normal I worried a little too, I had no appetite at all in the beginning of my pregnancy but as long as you get something in there you'll be fine.
Definitely eat what you can, your body and your baby's still needs nutrients but I wouldn't worry too much. I lost my appetite early on, just lost ten pounds though. I ate mostly fruit and toast. I'm 15 weeks now and have somewhat of an appetite but my portion sizes are half what they used to be.
Its normal. Just take your prenatal vitamins and try to eat as much as you can... at least healthy stuff. I lost 20lbs first 5months. I wouldn't eat. One time i lasted 3 days without eating because i couldn't take it.