Found out I was pregnant on the 16th of November 2019. Confirmed at the health Dept on nov. 19th

I don’t know when I concieved and I just know how to tell which day it was that I had sex before conceiving? I deff need to know and the stress is killing me because I don’t believe I am far enough for an ultrasound, but I also have a thought that I may have concieved before my ‘period’ in oct. October period was super super light, I had pain when urinating I thought I had a uti & blood was present in my urine a few days after my ‘period’ ended.