Should I be worried about how small I am?

I'm 22 weeks pregnant as of today. I have had alot of people coming up to me saying I'm too little, I'm not eating enough. Should I be concerned that I haven't gained much weight? I have gained a total of 1lb. I eat healthy, mainly fruits and veggies and home cooked meals. And I pretty much eat small meals ALL day. I can feel her kick and see her move CONSTANTLY. So she's very active. My fundal height is spot on. And my doctor says I'm doing very good with my weight. Just wanna get everyone else's opinion. I'm a 1st time mom, don't really know what to expect.