Hi Jb.
If it helps at all, I came off the pill for a bit a few years ago. I had been on it for 3 years. When i came off it, it took about 3 months to have anything like a proper period, and about a year to get back to a regular cycle. Sometimes it was about 45 days between, and lasted 9 days, some times 24 days and lasted 3 days.
Your body just needs to find a rhythm again. Thats not to say you cant get pregnant until its settled. You can! My Best Friend came off the pill in June 08, and was pregnant within 2 months, depsite not having had a proper period yet!