I hear you, I was the same at around 16 weeks... All you can do is take it in your stride as much as you can. Of course, on a bad day you're more than within your rights to make an inappropriate observation back about the person making comment 'gee I didn't realise you had so many grey hairs' or 'yes my belly is growing, but at least mines all baby'

It annoys me no end how many people think that because you're pregnant they have the right to make comments about your body, that otherwise would be completely inappropriate and even border on sexual harassment. There have been a couple of occasions where people (FIL being one of them) have asked to see my belly and I've cheekily responded with 'I'll show you mine if you show me yours'... it certainly put them back in their place.