Going about this the right way???

Ok so about 6 months ago I found out I got an STD from my then boyfriend (he cheated on me). I got treated and retested and it came back negative. I just had my 3rd date with a guy last weekend. I really like him and I am afraid he will not want to see me anymore if I tell him I had an STD. I decided I would go get tested that way when I tell him I will already have the proof that I am clean. I know he would want me to get tested and I'm completely on with it!!! I have an appointment today to get tested. My question is should I wait to get test after I tell him or before so I have the proof I'm clean when I tell him. I have NEVER been in this kind of situation before. I really like this guy and I'm so afraid of losing him....What do you think am I going about the right way??