Rude or no?

I'm not one who typically pays any mind to comments from others, particularly strangers, when it comes to my pregnancy. But a comment I received today just sort of rubbed me the wrong way. I was talking with a woman about my 6 year old when she realized I was pregnant. Then proceeding to ask if it was an oopsie. Just out of the blue! I'm assuming because of the 6 year age gap, which I didn't think was that crazy. I think what sort of upset me was that my husband and I had been trying for over a year and have had two miscarriages before conceiving this one. So I tried to do it sooner. Not that it even matters, as it's none of her business. But anyway...not sure if it's pregnancy hormones that have me extra sensitive or if she really was out of line. 
Just wanted to get that off my chest!