Should I test again?!

Stacey • Wonderful relationship, both military. Stationed in Washington state; Currently deployed. Originally from East Maryland.
So I took a test 2 days before I was supposed to have my period because we had unprotected sex about 2 and 1/2 weeks ago and it was negative, now I'm 3 days late on my period. Should I still take a test even though I did 5 days ago and it was negative ??? Thanks !