What Causes Delayed Periods Along With Abdominal Cramps?

I am 9 days late with my period. I have taken 2 hpt's with negative results. I a 42 and the length of my period have begun to change from 25-29 days with longest at 34 days. My last period was 2 weeks long which is unusual and I had intercourse after it ended which would be at the time of ovulation. I haven't missed a period unless I was pregnant. I continue to have aches associated with a period which I did have at the beginning of my three pregnancies and my cervix hasn't softend. I haven't been under any stress or any major changes so I have concluded that maybe I am at the beginning of perimenopause although the age the women in my family begin menopause is in the early 50's. Anyway, if you could give my some advice, should I make an apt. with my gynecologist or just wait?