is it mind over matter?

Rae

My period came 16th Sept and ended 20th Sept. My bf and I had unprotected intercourse on the 21&22of Sept. I had some stress related stuff going on for two weeks with my bf after our encounter then we had unprotected sex on the 15th Oct. my period suppose to come on the 14thoct but nothing showed. I did get slight vaginal cramps but nothing showed so I had unprotected sex on the 15th as I initially stated. out of anxiety becos of how my body felt...I took a p.test 16th and it showed negative, took another one @ 1:15am 18th showed negative again. Got scared cos of how I was feeling and I panicked and took one today around lunchtime and it said negative. although when I urinated I wiped and saw light pink. I thought my flow was coming that's why I took the p.test today. after that my napkin are clear(no light pink stain) I scheduled a doctor appointment for the 23rd Oct God willing. is there a chance I may be pregnant? according to the app i had sex before my ovulation or fertile days. but I'm still abit worried and confused to what's happening to my body. I've recently started having sex with my bf as of the first week of Sept 2017 so I'm not sure what's happening to my body. similar situation happen last month when my flow suppose to come but it did on the day it suppose to come on the 16th Sept (28day cycle) any help is appreciated