Earliest you can test?

My boyfriend came in me around ovulation a little over a week ago. It was a heat of the moment thing but we would be exited if I was pregnant. Anyways I’m now having a lot of nausea and head aches I want to test but I don’t want to start testing to early. What’s the earliest you’ve been able to test and gotten a clear negative or positive?? I have had other kids but I didn’t test until 3-5 days after a missed period. My period is suppose to come on the 11th.