You can buy DIFLAM from the chemist for swollen and infections. You have to ask for it as not out on the shelf. Boots sell it.
Warm Salt water will help with the pain, but not the infection. I would rinse with something such as listerine or crest pro health but the most important thing is to be brushing at least twice a day and flossing at least once a day.
take 2 advil and rinse like lynn said but you need 2 get to dentist
sometimes warm salt water rinses can help more than expensive over the counter meds. you do need to go to the dentist as quickly as possible because you need a cleaning and antibiotic to clear up the infection. if its more serious you may need additional procedures.