Bleeding after anal sex

Not sure if this is the right place for this but I had anal sex for the first time with my girl and, she enjoyed it at the beginning but since the day after she's been complaining about pain, it's been 3 days now and the pain is still there… I'm a bit worried, I want to take her to some sort of specialist o clinic just to check if everything is OK, but I guess this has beyond the scope of a gynecologist… Does anyone know about any other type of clinic o specialist I can take her to, to get checked? (we are from the UK)