What Causes Delayed Period And Watery Cervical Mucus?

I am 25 and I have been having a lot of clear, watery cervical mucus. I am not sexually active and I have already ovulated this month. I have missed my period for now about 4 days. I did some exercising Saturday and I got the cervical mucus Sunday and have had it since. Why is my period late and why do I have a lot of cervical mucus? Please Help!