i was away and wen i got back it was like black like it got burned or frostbitten or something i have no idea he uses it normally he doesnt seem to notice it but does ne1 have some suggestions as to what it may be?
The only way there would be frostbite would be if the tail was exposed to extreme cold. Obviously, the only way it would be burned is if a human did so. Did you gently attempt to see if it was a spot that would wash off? Can we get a photo?
If it's a devolving injury, you need it looked at ASAP by a vet, possibly be amputated but either way, it's EXTREMELY painful and needs to be dealt with ASAP. You'd see bone, most likely, though, so it doesn't sound like that.
That's not something to brag about, as your leg started to heal as soon as it was broken, meaning it started healing in the wrong position. They probably needed to re-set it, causing you more pain than you'd had if you went earlier.
Back to rats, they can't SAY when they hurt. You can't assume that because he squeaks when you touch it, that it's not hurting otherwise. He's saying, "It HURTS, please don't touch it," not that it only hurts when you touch it. If a rat is showing pain, it's a LOT of pain. They hide pain until they can't take it anymore.
You got rats, and it's your responsibility to take care of them when they are sick or in pain. It's cruel to know an animal is suffering and to do nothing about it NOW. Not in a day, now. Considering this happened yesterday, you're already waited too long. At this point, you may end up with infection, an amputation, or something equally as bad. Which means, it will be MORE expensive than if you'd tended to it when it first happened.