I've gained 5 pounds this month...

I'm 21 weeks, and since my last appointment a month ago, I've been hungry every 2-3 hours after eating!! It just kicked in out of no where. And not just hunger, but starvation. So I'm definitely eating more small meals throughout the day, and I've gained 5 freaking pounds in a month!! Which also means, I've gained 11 pounds in total so far. I feel like I shouldn't have gained that much, but how could I not with me eating so damn much. I'm not supposed to gain more than 20, so I'm nervous! Anyone else in the same boat??