I am 23 years old. My boyfriend and I had unprotected sex (our first time) back in June (2016). He pulled out and finished on his own. For about a month I have been paranoid that I'm pregnant. I don't have any obvious symptoms of pregnancy. I have been constipated, but I have IBS and went off my medicine for awhile so that probably has something to do with it. I have been feeling nauseated after meals this week, but I have also been having problems with sinuses and I was told by a doctor that mucus can cause nausea. My periods have varied. I have irregular periods anyway so I'm not sure about that. No breast tenderness, morning sickness, etc. I am on birth control. I also have PCOS and have low fertility. I took a pregnancy test about 3 weeks ago and it was negative. For some reason I just can't shake the feelings of being worried about it. What do you think? Could I be pregnant? I honestly don't think that I am but I still keep worrying about it. How can I stop being worried??

Not here to get negative comments or told to visit the doctor. I'm here for opinions.

Thanks.