I was pretty sure I started feeling mine from about 14 weeks-ish, but it could of also been my imagination . I just had a look at my pregnancy photos and there is one at 10wks and one at 14weeks and there wasn't much size difference at all between them. The next one at 18 weeks I am very noticably pregnant. I remember at around 14 weeks, it was when my morning sickness settled, and not much really went on pregnancy wise.

If you are worried, call your dr and see if you can have a quick scan to reassure yourself. Stressing out is the last thing you need to be doing (if you are) while you are growing those 2 precious bundles xx