Had protexted sex. Not even a day later it burned when I urinate, and one area of white pus or mucus. It's just on one side the size of my pinky.

? Bartholin's cyst. There are glands on the edge of the vagina that get rubbed during sex. The condom can cause irritation. You need an examination... Sit in warm water with a little salt in it and dry well afterwards for comfort. If it drains, you might feel better. You can repeat this many times a day, but do not let it get a lot worse, before having an examination.
Go see a doctor. Your symptoms are suggestive of urinary tract infection and you need antibiotics prescribed by your dr. In the meantime, drink lots of water and cranberry juice to ward off infection. Take care!