ovumahead I've just understood your nickname and am chortling away to myself 
Terrible headaches recently - at 16+3 but has been going on a week. Midwife not too concerned and reckons I'm a bit dehydrated, so chugging the water. Hard not to wibble a bit as I'm almost guaranteed a visit from my lovely friend pre-eclampsia but hoping I can stave her off as long as possible! It generally appears after 20 weeks anyway.
On the subject of scans I get them every 4-6 weeks cos I am super speshul
one of the good things about living near a big teaching/research hospital is the studies! I'm in one looking at factors affecting foetal growth (the pre-eclampsia with DD puts me at risk of small babies, though no-one told all 7lbs 12ozs of her). So I go in, they scan me and take the measurements. Next one is next Friday and they may well be able to see if it's a boy or girl! DH has given me permission to find out - just as well, since I'm so convinced this is another girl I need time to get my head around the idea of a boy...
Let's just be kind to each other on the subject of anxiety, please. I can't speak for everyone here but I have an anxiety disorder which goes a bit crackers in pregnancy. There are also some ladies here - me included - who haven't had an easy time with a history of miscarriage(s) and/or very difficult, traumatic births. I'd love to be sanguine and relaxed about everything but that isn't the way it works for me, and I think for several other ladies. So let's all be excellent to each other 