What's wrong with my vagina?

I have a constant burning and uncomfortable feeling down there. It can't an std because I have had sex with my boyfriend we Tried a while back but it hurt so he stop. And plus I've giving him head a thousand times since than so if it would be heroes or Athoner std I would of know! I've been dealing with this for about a month now. It went away for a bit but it came back after I started ovulation. But it still feels uncomfortable. I was looking down there and I noticed a bump in the inside of my vagina and I'm scared.