Welcome to HCM.
You have missed period of 10 days and pregnancy
test 4 times negative that is unusual if you are pregnant.
Tender breast, little spotting or abdominal cramp
are quiet common symptoms in early wk of pregnancy.
So better to do a USG for lower abdomen for confirmation of pregnancy. And consult with your doctor about scanning report.
If pregnancy is not detected on USG,then need to find out other possible causes of delayed period like emotional upset, Hormonal
imbalance, anxiety, eating disorder
, thyroid problem, ovarian cyst
,heavy wt or using any anti psychotic drug.
Take healthy diet,avoid stress and do light exercise.
All the best and tc.