kind of confused.

So I start my period in two days. I had unprotected sex on the 21-23rd multiple times. I never see my boyfriend he lives on the other side of the state. The 21-23rd was my 18-20th day in my cycle and the 21st was the last day of my fertile window. Now I have thick white odorless discharge in the mornings and I am constantly having to pee. My head is a constant headache. I have a punching feeling in my lower abdomen. I took a test the "5 days before your missed" kind within the 5 days. It was negative. I've also had a lot of stressors too lately. A dear friend shot herself so it's not like she just died. She felt so low in life she thought that if she was no longer around it'd be better :/ had a birthday party to plan. My boyfriend went back across state and so idk can I get pregnant on my 18th day??? Google didn't help at all.