Cat seriously injured or not??

Hi everyone,
I am trying to decide if my little guy needs to go to the ER vet or if he can see his regular vet in the AM.
So here is the story:He is 5 years old and strictly an indoor cat and even tho he has never spent any length of time outside he has occasionally escaped.He has never gotten further than 20 feet or so and never been out more than 30 seconds at most.
This past Saturday\\Sunday night I accidentally left a window open over night and he busted out the screen and left.So when we woke up we went looking for him but couldn't find him.TO make a long story short he managed to find his way back home yesterday afternoon.When he came home he OK except being very very dehydrated ,dirty ,hungry and a approx1.5 inch scratch on his leg.The scratch was not bleeding and I cleaned it out real well and it is not infected and looking good.
However since then I have noticed today that he is really not using his tail there seems to be a little swelling on the base of the tail and touching it or moving the tail seems uncomfortable.I think he is in pain because his personality is subdued and he is sleeping a lot(more than usual and yesterday I brushed it off to being out for days.).He is eating well drinking using the potty.He is walking well altho I *think* a little slower and steps a little light on the injured foot.He does jump on the counter where his food is and on the laundry pile in chair to sleep and on beds to sleep.I see no misses or hesitation there.
So how worried should I be?
Thanks
Kat

My opinion only, I am not a vet... Even though I wish you had taken him to the vet in the afternoon when he came back, since he is eating, drinking waking, jumping, using the litter box, I do think he is ok to wait until the morning - but I would take him as soon as the vet opens to make sure there is nothing wrong, no infection, etc.
Keep an eye on him - if he becomes lethargic, then it is time to go to the ER. But, you know your cat best, so go with your gut feeling too...

Yeah I wish I could have to I had been looking for him all morning I didn't find him and as I was walking out the door to go to work(new job after being laid off for a while could not miss but was late) he comes running across the parking lot to come home.So I took the time to feed him clean his fur and the scratch.before I left I also forced a little water into him and had my daughter do the same.When I came home that night he looked like himself bright eyed and alert.The scratch itself shows no sign of infection(no swelling puss doesnt look angry)he is just extra sleepy and not as social with his siblings.But when he hears something he looks around he enjoys to be petted etc.He just doesnt seem to want to move or really play.The only swelling is the base of the tail even that is minimal if you wouldnt know him you couldnt tell and he doesnt raise it or seem to move it.Aside from the scratch there is no sign of obvious injury(no other bites scratches swelling etc).
Kat

How is the kitty doing? Did you take him to the vet?

I am glad you cat found his way home and sounds like he got into some trouble, poor guy. Hope he is doing better today? I definitely would take him to the vet if he was my kitty to be checked out.

(I'm not a vet either)
If possible you may want to take him to the vet to be doubly safe. I have a stray that stays outside and gets in random tiffs with other cats and goes off on long jaunts for 2 days sometimes. He's come back with some small war wounds, but safe is better than sorry.
Like others said keep a good eye on him and make sure his appetite is good, bathroom habits ok. Has he had ALL of his shots? Keep an eye on his injuries, because they can get bad easily, even when they look like they are healing (Like puncture wounds)

Hope he is doing better today. Sounds like you should put up some picket fence style window protection, like my mom and dad did to me when I was little!