Please help, I’m scared and confused

I’m three days late on my period. I have thick, white discharge that looks like yogurt and has no specific smell. I have taken two pregnancy tests and both have come back negative. I last had sex on the 30th of June, before that the 23rd, and before that the 12th and the 13th. During the 12th and 13th I was ovulating, and used a condom. the 23rd and 30th, I used the withdrawal method. I have bad cramps on and off, and constipation. My period is usually regular and my cycle has always been 28 days. Im confused as to what is going on and I need help understanding. Am I pregnant?