Hi,
Welcome to the forum. I am really glad to help you out. These cramps and heaviness which you are feeling can be due to pregnancy or sometimes due to premenstrual syndrome.
However, it makes sense to get the serum pregnancy test done. A serum beta HCG levels should be done which is a much more sensitive test compared to the urine test for pregnancy.
If the serum beta HCG test is negative, then the possibility of pregnancy is virtually ruled out. If pregnancy is ruled out, then other causes of the delayed periods needs to be looked into.
It can happen because of hormonal imbalance, increased stress, eating disorder, increased smoking, alcohol or caffeine use and medical conditions like PCOS, fibroid, polyps and endometriosis.
An ultrasound of the pelvis will not only help in ruling out pregnancy but will also facilitate in looking for other causes of delayed periods like PCOD, endometriosis etc. Please do consult a gynecologist also for the same.
I sincerely hope that helps. Take care.Please do consult a gynecologist for the same. I sincerely hope that helps. Take care.