Thanks for the reply Ria, I just like to have a bit of knowledge behind me before hand as I dont really trust vets in regards to treating small animals.
Trip to the vet didnt start well, I handed her over and explained where lump was and that she wasnt very active, often just sitting about rather than exploring/climbing. He asked her age and when I said around 3/4 months he replied with "well they dont move about much at that age"
Iv had 11 Syrians now and they have all been extremely active at 1 year old never mind 3 months. Anyway they have prescribed anti biotics as presume it must be a skin abcsess. Got to put 0.2ml in her water for next 7 days and hopefully clears up.