No periods for a year!?

I recently have had no periods for 12-months, then in November I have one. I thought I was going through menopause, but now I am wondering what is going on. I am 50 years old. I haven't had a pap smear in years. Why nothing for 12-months, then I have one. I am waiting to see what will happen in December. Any suggestions? Should I see a Dr?