Late Period, Negative Pregnancy Tests.

I am currently at day 43 of what is usually a 36 day menstrual cycle. I experienced spotting for 2 days on cycle day 27 and am currently 5 days late for my expected period. The only time I have had intercourse over this cycle was on day 17. I have been experiencing mild abdominal cramping, bloating, breast tenderness that comes and goes, and most recently a cramp-like pain when I urinate on the right side of my vagina. I am not on birth control. I have taken several pregnancy tests since I experienced the spotting, the most recent being yesterday morning, and they have all been negative. I do not have insurance and would prefer not to see a doctor unless absolutely necessary (poverty, yay!). What could be the cause of this, and would I be safe to wait this out or should I schedule an exam?