Could it have been too early?!

My parented and I had sexual inter course 20th & 27th of september and again on the 15th of October (unprotected). AF was due of the 13th. I tested on the the 8th because i have been feeling very different lately & having so many signs and symptoms and I feel within myself asthough I am pregnant- so I tested and got a BFN then tested again on the 13th (day AF was due) & still the same result. Could I have just tested too early? & should I go do another test? 
Thank you ladies.