Thanks for the query.
Since you are not on any contraceptives and have missed your periods, there are chances of you being pregnant.
I recommend you to wait for 1 more week and get a urine pregnancy
Also an ultrasound
to be more sure.
Delayed periods could be due to emotional stress, hormonal
imbalance, thyroid problem, ovarian cyst
I advice you to practice safe sex and refer to a Gynecologist to rule out the above mentioned causes of delayed periods.
Hope this helps,