Speech delay?

Laura

My little guy is 22 months old. As we get closer to his birthday in October, I find myself dreading it. He is the most amazing little boy who I love more than anything. But everywhere, I read that my boy should be saying 50 words by age 2. He doesn't say anything but Da! He's so skilled at playing with his toys, stacking,playing etc. But he just never speaks.

Are kids really speaking so much at this age? Is he really behind? I read him 15 times per day. I narrate everything. I know he can hear me. Should I call the doctor now or wait for the 2 year appointment?