Suggest Treatment For Red Raised Painful Area On Shin After Injury

My wife had a softball hit her in the lower leg, just above her foot on the outside of her shin, about a month ago. She had a large deep bruise at the point of impact. The bruise has healed and the pain has subsided quite a bit, but now there is a large red raised area, warm to the touch at the site. Her breath smells like infection too. The skin is tight over the area and there is a little pain when palpated. I think it is a blood clot and is infected and she needs anti-biotics. I jokingly told her I was going to lance it for her. She didn't like that. Of course, I was kidding. What do you think?