Could any of this have caused my missed period? (read details)

The first day of my last period was May 15th. Through June I was getting kind of stressed about money situations, then mid-June I went on vacation to the East Coast. Around June 20th, when I came back home I got sick. Coughing, sore throat, runny nose, etc. That lasted unitl the end of June. I never got my period in June. I have had protected sex twice since I’ve been back from my trip. I HIGHLY doubt I’m preggo, I know my body pretty well and have been pregnant before.