My breast feels tender. i thought i was about to get my period but it didnt end up coming and they are still tender. i did a few pregnancy test. every time came back negative. could i be pregnant? i dont understand whats happening?

Home pregnancy tests are very accurate and not affected by foods, herbs, common illnesses, sexually transmitted diseases, or medications. A correctly done urine test gives a reliable result 3 weeks after sex (3 weeks after when conception might have happened) or 1 week after missing a period. If done sooner, a positive result is likely real, but a negative result may be due to testing too soon.