High chance at pregnancy?

I got my period on June 4 - 10. Then I had unprotected sex June 17, and June 19. I've been feeling moody, tired and a little off lately. I feel like I can't focus lately and I'm very forgetful. I also went to get a new bra the other day and found out I went up a full cup size! On June 27 I woke up at 430 am and was soaked in sweat (night sweat) and went pee since I've been having frequent urination lately. After that I realized I was dizzy and felt very sick and I puked twice and the next day on June 28 I had brown discharge on my underwear (just a lil). Then today, June 29, I had a nickel size of brown blood or discharge on my underwear and I have cramps but nothing else so far. My period isn't due till like 4/5 days. Could this be implantation? Does this sound like pregnancy? P.s. The past two brown discharge days is when my breasts have been hurting the most and I'm just developing headaches :/ does my timing seem right?