Period, pregnant or hormonal imbalance?

Patient: I had a tubal ligation procedure in 2007, so unlikely to be pregnant, however , last week (7 days before my period was due) I began spotting brown blood. I do spot before my period for a couple of days, but this was early even for me. On the fifth day, I passed two medium sized clots and the spotting finished. This morning, I bled bright red blood for a very short time after sex and now I have a watery pink discharge. My period is not due till Wednesday. I have had very sore, veiny breasts for a few days, with tingling and shooting pains. I have taken a pregnancy test which was negative. .

Doctor: