chances of pregnancy?

My husband and I are TTC and had sex two days ago and yesterday I had quite a bit of clear discharge and today it's more creamy and white. (Sorry if that's a bit TMI) I'm supposed to be ovulating today. How soon could I take a test? 
Also, this is the first time I've ovulated after coming off BC. Is there still a chance I could get pregnant? I've heard it takes some time to get out of your system though.