I think your starting menopause.
I agree with msniki....that started to happen to me when I turned about 41-42. I always had a cycle of 28 day and during my early 40s, my cycle started getting longer and more irregular. I would go 30 something days inbetween periods and I would take a HPT hoping to be pregnant. Like Araun stated, try taking a HPT and if your period still doesn't come, go see your doctor.
You should take another pregnancy test in 7 days, if you think it is possible that youre pregnant. When you have'nt had your period for 2 months you could talk to a doktor.
good luck
You could be getting ready to go through menapause. Your close to the age where your periods would start to get irregular. Any other symptoms? Weight gain, pain, discharge? If anything, see your doctor on any changes.