How can I prevent my gnat bite from itching so much?

I have really bad gnat bites, and one on my arm is getting really bad. It bulges off of my arm and is a blotchy shape, and if you was to prod it its really hard. It is oozing as i kind of itched it too much... I don't have any cream suitable to put on it and its really annoying and itchy! My dad wont buy me any creams to put on it as he thinks its best to just leave it alone and it will go away by itself. Is there any way i can make it less itchy/stop oozing with regular household items?