8 pounds!

I am 21 weeks 3 days and yesterday I had a doctor's appointment. I knew I had gained weight, I can clearly see it and feel it. Unfortunately I gained 8 pounds in 4 weeks. The Medical assistant that weighed me made a comment, but my doctor didn't say anything. Honestly my doctor was in the room for all of maybe 8 minutes. She rushes. I was actually going to mention it to her, along with other questions I had but she rushed out before I could. Has anyone else had rapid weight gain? I started out overweight and didn't want to gain a ton! I have gained 14 pounds so far. This is my second and with my first I gained 50 lbs!