Ovulation question

My boyfriend and I are TTC #1. My period started on the 12th and stopped on the 17th. All the ovulation calendars say I start this week but it seemed like it began pretty much on the 18th-today with clear watery(fairly heavy and now dwindled down) CM. is this at all possible to happen that soon? I also had pain near my right ovary like I usually get when ovulating.