hi there, a delay of 2-3 days is not a cause of concern and sometimes due to stress
they could be delayed. Take a urine preg test with early morning sample and if it is positive then visit your doctor who will be able to prescribe medications or suggest other ways, if negative then you need not worry and relax you will get it eventually. If you are not keen on getting pregnant now then it would be wise to go for a long term contraceptive
method like an intrauterine device
. It will save you this tension. Take care.