5-6 wks? Is this normal? Baby #2!

Natalie • 💕👶🏻🌈

So today I had my first doctor appointment for baby #2. I previously had an IUD and removed it in October and got pregnant right away, or so I thought. Going off my last period (which I only had one since I removed it in October) it said I was 6wks 1d. Which seemed right, but today the doctor said the baby looks like it’s actually 5wks so there was no heart beat yet. Yesterday and today I had light bleeding/ spotting red, but they said it could possibly be normal/ok since there’s not cramping. So I was just wondering if this has happened to anyone else? Meaning, have they gone back on how many weeks you are and push your due date forward? I’m just a nervous wreck and feel like something is wrong, mostly cause I feel so normal!!! Besides some tender breast and headaches everyday, I feel fine. Please share your opinions, experiences, and good vibes! I really need them😭 I’m just riddled with anxiety and am scared baby stopped growing or I might have a miscarriage. I pray not but it’s so hard to not think negative. I’m just trying to steer my thoughts to good ones! Got blood test done but wont get results for another week. Due date was July 30, now August 5 possibly.