Symptoms you may be experiencing can be due to hormonal changes, which may not be indicative of pregnancy. An irregular period can cause the hormone levels to fluctuate, leading to tender breasts, bloating, and mood swings. Stress, diet, and lack of exercise can also be the reasons why your body is affected this way. Try managing stress, eating healthy, and gentle exercise to help balance your hormones.

In this case you should go for second opinion of another experienced doctor. They can evaluate your case and then you can come to a conclusion.

Possible side effects of the morning-after pill include changes to your menstrual cycle, however, do not expect these to be the case with the pill. So it's okay if you're late. Pressure or other causes may be considered by the mind as well. Your negative pregnancy tests suggest that you are probably not pregnant.