Early period? STD?

For the last 2 days I have had a stinging pain on the lip of my vagina, no discharge or discolouration though. It kinda just felt like a cut and now I am bleeding 3 days before my period is meant to come. I have also gotten sick with flu like symptoms but haven’t had unprotected sex only have given oral sex and swallowed. Is this just a coincidence and have I started my period early?