I Am 16days Post Ovulation. Took A Test At 15day

I am 16days post ovulation. Took a test at 15day post and results were negative. I have felt cramping here and there but nothing serious. Had a headache 3days ago and went away. I used generic walmart morning after pill but did not take the whole thing after having unprotected sex. A week later I had unprotected sex again and took another morning after pill. Could I be pregnant? My cycle is normally about 23days on average. Pretty much regular.