IMPLANTAION BLEEDING AT 4DPO???

On 8/25 when i wiped i saw two tiny spots and then thw rest of the day nothing clear even pee was clear. I did throw up some food but I think it was because of just the food lol today 8/26 I just went to the bathroom and wiped and it was a very light pink and my pee was a little coloured as well. I hope that's implantation bleeding but idk because I'm 4dpo and my AF isn't due till next month on the 5th. Is it possible to implant at 4dpo? I feel fine right now like no cramps just tired that's all..