Am I pregnant? And when should I test

im not sure if I could be pregnant and when I should start testing I had sex on October 8 and then ovulated October 15 I get cramps when I ovulate that's how I know when I do and then I started getting cramps and really bad head aches and nausa and a sore throat week after I ovulated and i started getting cramps a week before my period should start and then they stopped and started again 2 days after my missed period along with brown discharge which I've never gotten before Im not sure if that could be implantation bleeding i only notice it when I wipe it doesn't get on my underwear at all and its a very small amount. I'm also not sure about when I should take a pregnancy test i track my periods and I should have started on the 27th and it's the 29th