Don't be scared Tenar. Babies do grow bigger in the last trimester, but as the others have said, scans can be pretty inaccurate when it comes to predicting size. I can't tell you how many stories I've read where people have had c-secs for 'gonna-be-huge' 6 or 7 pounders.

Besides that, you've said you think you're actually closer to 36 weeks, you say you're not hobbit size yourself, and to be honest often a heavier baby's weight is in length anyway, which isn't really a huge problem in terms of getting it out. Plus babies are pretty squishy, to help them get out. My first bub was 9lb4oz, I'm not the world's hugest person, and I birthed him just fine. I also know of people who've birthed much bigger babies just fine too.

Wishing you well for these last few weeks.