Am I pregnant!! Please help?

I lost my virginity for the first time during the month. I made a stupid choice by letting him put his in me for a minute without protection. Immediately after i began worrying i may be pregnant so i've been VERY stressed all month. I am a week late for my period and i've taken COUNTLESS numbers of pregnancy tests. I took a digital one this morning and yesterday morning and they were the kind that u could take 5 days before your period. I figured since im a week late it should give me a trusty answer. Well they both said i was not pregnant. But i don't get it because i have sore , INTENSE cramping, and no discharge. I've been like this all week. I did think that maybe it could be an ovarian cyst, since i have had one in the past. But the fact that i've never been a week late for my period really scares me. You'd think with all the tests i've taken i would feel reured but i don't. What do you t hink this is!!??