May be pregnant 😔

May 17th I had unprotected sex with my fiancé. He did pull out...but that doesn't mean nothing got in me. So I believe I was due for my period a few days later. Around May 22. I'm not completely sure. I took 2 tests on Satueday which would be 13 days after sex. Both negative. I wonder if I took them too soon? Cuz I still don't have my period. Which makes me over 12 days late. I'm never this late. Definitely scared I'm pregnant. Has this happened to anyone where they just got their period late due to stress? I have been stressed and a lot of change has been happening in my life so I hope it's just that. 

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