Fundal Height?

Does anyone know if this is an accurate diagram of fundal height during pregnancy? It's the only one I was able to find that made any sense to me, I guess it's because the statue looks like an actual person and she has a similar body type to mine. I felt my uterus for the first time around 11 weeks however, I'm currently 13 weeks and 3 days but I don't feel like it's grown any since then and some days I can barely feel it. I know everything is ok with the baby because I listen to the heartbeat with a pocket fetal Doppler and I can feel some flutters every now and again but I'm still worried my uterus isn't growing like it's supposed to. Maybe it's because I have a decent sized torso and a little bit of flab so the uterus has some room to grow in there before it pops out, I don't know.