Stressed and Caffeine, Late Period

Here's the deal... I had sex the day after I finished my last period. It had started May 5th. The guy was fairly drunk, and had problems keeping it up, but when he did, I wasn't as turned on anymore. Sad thing is, I was so bone dry that the condom broke. I didn't notice for a while, but I stopped him when I did. He did NOT ejaculate inside me. I've also had protected sex several times in the last few weeks. My period was due on Saturday, and today is Monday. It's two days late. I am usually irregular, but I'm super paranoid.

I've been taken about 600mg of caffeine a day (pills and coffee) to stay awake for my extremely stressful, intensive online classes. It's Monday now, and I'm not having any painful cramping, which usually signals the beginning of my period when I do get it .
I am so, so paranoid I'm pregnant. Please help!