Had unprotected sex about five weeks ago, and got itchy rash on my penis. what did she give me?

Maybe nothing.: It could be an allergic reaction to something, such as a spermicidal gel that she may have used, or a direct irritant reaction. If you really suspect an std, see a doctor and get tested. And i hope you learned your lesson about unprotected sex!

No way to know.: If you have a problem after unprotected sex, you should get seen, examined and treated appropriately. The risks are too high. Use protection! now you know!