Confused

I am 31, I have a 10 year old, I've been with my husband of 2 months 4 years now and we just started trying to have a baby this morning...we have never tried in our 4 yr relationship to have a baby and my period is like clockwork always on time & never any spotting...my next period is supposed to be here in 4 days but I am spotting right now...I will be checking if I'm pregnant in a few weeks with my fingers crossed...I don't remember how it happened when I was younger with my 10 yr old  besides that I was on my period when I conceived in 2004