uterus size

I feel like I'm driving myself insane. I'm 16+3 right now, and I've looked at charts online that show uterus size at different stages, and what I can feel of mine isn't "as large as it should be". Of course I'm not a physician and I could be wrong lol. I've had 2 perfect ultrasounds, heard baby's heartbeat and seen a lot of movement, and our next appointment is in 5 days. I have absolutely no reason to believe that anything could be wrong (no cramping in 6 weeks, no bleeding at all), but I can't put my mind at ease. I ordered a Doppler that should be here on Friday, so hopefully I'll be able to find baby's heartbeat and feel better. Am I crazy? 😜