Yup, very much so. Mine started at around 16 weeks- well thats when I noticed it anyway, they may have been leaking before that, I dunno.
I called MW who said it can really start at anytime, as it depends on the hormones.
Some start earlier than others, and some dont get it until 6 months. I was horrified when I noticed I had it at 4 months, but you're not alone.... I started at around 15/16weeks too, and it just gets worse and worse, so be prepeared hun x