21 weeks no weight gain!

I’m getting really worried and depressed about this seriously. I know people don’t want to gain weight but I’ve been reading it’s not normal and not healthy. I want to switch OB’s because she rushes through everything never giving me enough time to discuss things thoroughly. I don’t think she’s paying any attention to my weight to be honest it’s never brought up but I’m the one who notices at every appointment that I’m not gaining ANYTHING. Not even one pound this whole pregnancy so far. And then I read this online (see pic) so I’m kinda freaking out a little..😒😒😒