Boss just called me out on my pregnancy

I submitted a sick day request today to my supervisor for a few weeks from now, which he passed along to our HR department.  I then got a text message from him immediately afterwards congratulating me on my pregnancy and telling me not to worry, that he would keep it under wraps.  When I responded saying that it was rather presumptuous of him to say that, he called bullsh*t on me and told me there was no point in dodging the topic.  I haven't responded.