It's also possible you are dealing with a cyst. I've had some ratties develop cysts that required veterinary care (one had ruptured, drained, and the skin necrotized very rapidly. The vet debrided the dead skin and closed up the wound with skin glue, and provided a course of antibiotics), others I've managed to drain, clean out, and treat myself successfully, and even a couple of lumps that disappeared on their own (the rats were on Baytril for resp. symptoms anyway... I believe these lumps were probably small cysts or perhaps swollen glands (?) that simply abated on their own with the antibiotic treatment).
Don't worry, Honey... get the lumps checked by a good, qualified vet who knows and cares about ratties. Whether the lumps are cysts, tumors, or something else, it's entirely likely they can be successfully removed/treated and that your ratties will be just fine!
