STD BIG Problem!!!?

I went to the ER today because I was feeling like crap. When I went there the specific reason was because I have a sinus infection and I also told them that I had a little problem urinating. She looked at my and told me that it "looked like I had an STD" because of skin marks that are on the head of it. But I went to my regular doc and they gave me a physical and checked me for STD's about 3-4months ago and my doc nvr called me back so I thought everything was ok. I recently did something with my girl and now I am scared to death that I may have given her something. The ER took my sample to have it checked so I am not sure if I do have an STD; I am just scared because the doc said it looked like it could be. All at the same time however I use a bizarre method when I masturbate myself that has to do with the head of my ... I am just so scared right now... PLease HElp!