Do i have an STD? I dont think so but can i be wrong?

So maybe i have an std I'm not quite sure. I searched warning signs. And so far all i have are Itching and burning. But That was from a scratch and I the burning is because the itch cream gave it a burn mark I noticed. And is it normal to get a pimple down there every now and then, I know its a pimple i popped it?