Sometimes, if you tubes are only burnt they can grow back. It's rare but it happens. On another note, you might be going through early menopause. I would definitely talk to your Dr. Good luck.
It is possible to have a random month of amenorrhea. Also (not to be insensitive) as you get older your periods can become unpredictable as you move closer to menopause. My mother started when she was 45 and is now 57 and still has an occasional period.