okay so last month i had my period early i usally have it around the end of the month but instead i had it at the beging and it started on the 8 and was gone by the 10 but it was more of a spotting. i still have not had a real period and in my lower abdomon i have pain mainly on my right side, that started arount the 8 i went to the er because i had a knot in that side they told me it was a lip note and they did a pregnancy test it came back negitive i also did one the day before yesterday and as well it came back as negative, the knot is gone now its just pain but not a constant pain. what could it be and what should i do?