clomid mid-cycle spotting normal?

Ch

This is my first cycle Clomid. I'm on cd19 and I started spotting this morning. I got a pos opk cd17. I called my doc and he has me do blood work today. He said it could be a early period, I sure hope not though. Have any of you ladies experienced This? was it due to ivulation or early period. isn't cd19 to early for progesterone test if I possibly ovulated 2 days ago?