Pregnancy help

Af
Hi. I'm due for my period on the 13th of November, which is the 30th day pf my period. on my 10th, 13th and 14th day of my period, I had unprotected sex. I'm on no birth control either. I've been experiencing a metallic taste in my mouth, back pain and fatigue. Could this be pregnancy? And if yes, when would be the right time to test for it?