Trying to conceive

Me and my boyfriend have been ttc for 6months in counting, last month we had sex two days in a row on my fertile days and the third day I was ovulating. I am three days late but yesterday I tested and I got a negative, it ruined our whole day. I still haven't started and I am pretty antsy to take another test but I am pressing my self to wait a few more days. I am wondering if it could be possible, if anyone has had a experience like mines or close to it. It is now three days after my missed period. I am still experiencing light cramping and my breast are extremely sore.... I could really use some feedback!