I will try to give as much information as I can I started my period when I was 10 and it was always irregular it would come every other month sometimes a week late days late and ONE time it skipped 2 months well my last period was on September 10 (at this point my period was coming every other month)but on october 13 my boyfriend and I had unprotected sex he "pulled out" well I did not get a period for october I kind of started to worry so in beginning of november I took 2 pregnancy tests and they came out negative but I continued taking them until about december 1 (still negative until this point) on december 4 I went to a teen clinic (im only 17) and it is confidential and they did a pregnancy test and pelvic exam my test came out negative and the gynecologist said I was fine she even asked if I wanted to get birth control condoms any contraceptives I decided to get on birth control but I still don't get my period today is the 20 of december and I have gained atleast 5 pounds in the last month and I really don't know if my period is just really late or if I could be pregnant I get cramps mainly on my right side I don't have frequent urination or nausea or vomit just cramps and have gotten a bit fatter