Awhile back I too found a lump on Fluffy while petting him. We too rushed him to the vet who felt it and at the time didn't seem to concerned. She told us to keep an eye on it, make sure it didn'g grow bigger or move.

We checked it every time we brushed him, and one day my husband asked me what side the lump was on, again?? We both felt Fluffy, and neither of us could find that lump! Yeah! And we searched & searched

So, do not rush to conclusions, or into surgery just yet. Give it some time, and see what it does. Sometimes they get bumps & bruises, but it is under their skin (ours show on top). I know it is hard to be patient, but hopefully this lump will go away on Luna, and we all worried for nothing But we will be keeping all fingers and paw's crossed, just in case......