Periods

I'm 34 years old and my cycle is either from 25-27 days and period last regularly 6-7 days. Well, this month it came 3 days early and only last 3 days. Does this happen because I'm getting older and it's just going to get harder to get pregnant or is it possible that I may be pregrant now. I know I should see a doctor but I'm just scared to know that it's something serious and that I'm not pregnant and may never be able to get pregnant. Any ideas?