Hello,
I have a question for you all. I am a 25yof, have been on birth control for about four years but was on a 5-week round of doxcycline in late April/May. My boyfriend and I use condoms in addition to bc and last had sex on June 1. I had a regular period on June 5-10th. A week and half later I had about 5d worth of brown discharge and then July 3, when I would have gotten my period, I got probably the lightest period in the world for about four or five days. I have had cramping and low back pain for about 3.5 weeks. I took a pregnancy test yesterday and it said negative.
Besides the antibiotics, during that time I was training pretty hard (on average 1-2 hours of cardio a day plus 45min-1 hr lift) and I dropped about 11 pounds.
The only other complication I can think of is that in early April I had a colposcopy and biopsy for cervical dysplasia which came back as being very mild. My doctor said he wanted to leave it to see if it resolved itself and to follow-up in six months.

What are the chances that I could be pregnant without a preg test coming up positive at this point? I have read that cysts can result in similar symptoms.

Any thoughts?? Thanks for any insight!