I haven't had a period in 2 weeks, i've had a blood test and urine test for pregnancy both negative. what can be the cause of my situation?

Failed ovulation: I assume you mean you are 2 weeks late for your period. Any woman may not release an egg, & upset the delicate cascade of hormones which lead to our period when an egg is not fertilized & implants to become an embryo (baby). Consider your past period history: have you skipped/missed/been late for periods before? If so, this could be normal for you. Missing a period for 4 weeks=dr. Visit.