I'm in the same boat, scruff. I thought I'd have a legit preggo belly by now, but not really yet... Not in a remotely obvious way, anyway.
I work from home, so tend to wear yoga pants and whatnot most days, whether pregnant or not... Right now I'm still wearing my "transitional" non-maternity (but flowy-er) tops when I "go somewhere" and otherwise just wearing my basic knit tanks/tees with maybe a hoodie to hide the slight paunch/mini belly. That's about it. I bought a fair bit of maternity clothes from Old Navy's sale and the big consignment sale I went to, but they look stupid/too big still (IMO). I thought at least by 20 weeks I'd be in them, but I'm 19+2 today and no end in sight... Maybe by 22 weeks or so?
same as you two, scruff and buko! everything between boobs and hips seems to be moving outward at the same pace, so there's no roundness to it yet. still wearing all my normal pants, too.