Late period, some answers please?

So, my period is about 3 or 4 days late now. I have been very stressed this month, it's been a rough one. I was out of town, dealing with my alcoholic/drug addict father, and coping with the loss of my job.I had my period last month, and my boyfriend and I haven't had any kind of this month because of my being out of town, so I don't think I am pregnant, but I am feeling so bloated and crampy and irritable and I just want my period to come! Why is it so late, and why won't it come? What should I do? I am almost always like clockwork, 28 days, but I have not had a month this stressful in a long long time. I am going crazy, I think!