Cervical mucous question

I stopped taking my birth control about 2-3 weeks ago. We are not try to have a baby right now but I wanted my body to get back into its own cycle again before we start trying in like 6 months. We had sex on Monday and used a condom. Ever since I've had absolutely no cervical mucous even though I'm on my "fertile week". Any ideas what could be going on down there?  Thank you!