Before anyone says "take him to the vets", he was there on friday (yesterday), and is booked back in for monday morning. Took him to the vets yesterday as he just wasn't well and acting out of character (being clingy and soppy and sleepy), found no obvious physical signs of anything but did have a high temperature. I was given antibiotic tablets to give him one a day and to take him back on monday. Got home, gave him a tablet. Few hours later he was much brighter and happier, went and bought a thermometer and that evening his temp had dropped to 38c. Today he is more or less back to his normal self and his temp is now 37.5c. But now I have found a "lump", just below his spine. It looks like a tick, except that it doesn't. Its the sort of shape of a tick, but its sort of a see throughy white colour like a cross between a water blister and a wart, and it is quite hard not squishy. Tried to take a photo of it, but he wanted to see what I was doing and wouldn't stay still.