Hi I’m 20 years old and last year I went to the hospital because of a extremely uncomfortable cycle Turns out I have a cyst on my Left ovary fast forward to October of this year 

Had unprotected sex on the 15th/the 16th everything was fine until 3 November I started my period and it was bright red. I am not supposed to start my period until November 8. 

Now, could it be bleeding from my cyst?

Could it be implantation bleeding?

Or could it just be my plain old period . Coming early ?