Is it and STD?

Hi,

i had oral sex a week ago last saturday and the friday later i had irritation around my genitals. This has continued for a few days now, and i went and bought the yeast infection cream, but I'm still worried i caught something. My mouth has also been going crazy - the taste buds at the back are huge and red, and the roof of my mouth had odd red patches with small white dots on. Ive had a cold for over two weeks now, which might explain the soar throat, but I'm confused what these other symptoms could be. Can anyone help? Thanks