It is not normal.. you shouldn't be gaining any weight as of right now.. I'm 16 weeks and havnt gained a pound..
It's important to stay fit during pregnancy, because if you gain too much weight, it will be that much harder to lose it after the baby!
I'll tell you what my doctor told me and my fiances family females told me.
Don't fuss over weight gain. I have only gained 11 pounds and im 31+6. If you pack on 10 pounds or 50 pounds so what? As long as you eat healthy it shouldn't matter.. just monitor how fast you gain. 10lbs gain in 4 days is cause to see a doctor for example. If you are worried talk to your ob they will give you a meal chart of good foods and portion sizes.
It isn't normal talk to your doctor at your next appointment. I'm 9 weeks and I lose about 12 pounds. I eat every three hours but fruit or drink fresh fruit juice. Its very important you eat healthy.
Every woman is different. Every matabalisim changes differentz some people lose weight, some gain, some stay the same. Eat good, and exercise is important, the amount of gains isn't important.