The answer to 'why is my rat bites' is that rat bites are typically caused by an infestation of rats in your home. Rats may bite if they feel threatened or are trying to protect their territory, food, or young. Common symptoms of rat bites include swelling, redness, and pain at the bite site, as well as potential risk of infection.
The best solution is to address the underlying rat infestation. This may involve setting humane traps, sealing entry points, and removing food sources that attract rats. However, if the infestation is severe or you are uncomfortable handling the situation yourself, it's best to call a professional pest control technician who can properly identify and eliminate the rat problem.