Cant take much more..

My boyfriend and I moved into a basement apartment together with my Golden Retriever.. He loves cats so we decided to get a kitten to keep my dog company.. The cat LOVES the dog. They play together, sleep together..

Meadow (calico kitten) is 18 weeks old. She is a good kitten. She has attitude and is really feisty but ive been told that thats a calico. She has always been good about using her litter box. But recently she has been peeing everywhere.. She peed on my favourite chair, peed all over the dogs bed several times. and now that Ive taken all that stuff away she has started peeing on any clothes that are left on the floor.. She does use her litter box no problem. But recently has started doing all this..

Like i said we live in a basement apartment and the landlord has no problems with pets but I dont want the basement to start smelling like cat pee..

I did recently change her small kitten litter box to one with a lid so she stops spraying litter everywhere.. and she uses it no problem. Im wondering if thats the problem though.
My boyfriend says its jealousy issues because the dog gets to go outside and the cat is an indoor cat.She does sit at the door and cry and cry when Chloe's outside.
We do want the cat to be able to travel with us.. We do alot of traveling and we take her with us almost everytime.. She is really good when we go places. But im wondering if shes peeing because of that! Maybe because we take her to another home which is larger and she has free run of the house, then we bring her back to our litte apartment..
Im really at wits end with her.. I love her to death, she is a real sweety. But she cant keep doing this or we are going to have to get rid of her. As much as I dont want to!

Im not a cat person. The last time i owned a cat i was 7 and we had to get rid of it cuz my brother was allergic.. So i really dont know what to do.. How do you train a cat with attitude.. or any cat at all.. they arent like dogs at all. When meadow gets in trouble she will seriously walk along the back of the couch and swat at your head while your sitting there!
HELP PLEASE!!

The very first step is to visit your vet. Radical changes in litter box behavior can indicate a health problem so you want to rule that out.

How long ago did you change the litter box? Does she urinate in the new box or only defecate? Some cats like two boxes one for #1 and one for #2 !

It might be too early and someone else probably knows better than me but there's the possibility that her new behavior is related to hormones as she goes from girl to woman or something like that.

Do you still have the smaller kitten box without the lid? Put that one back out asap and see if that helps. Maybe she just doesn't like the cover.

Cats are very sensitive to any litterbox changes - location, type, size, litter type, litter brand, etc.

Vet visit ASAP, please.

And please stop taking her everywhere - cats do not adjust to change well at all, because it stresses them out, and stress can cause health problems like urinary tract infections - very, VERY few cats can handle being travelling cats.

You may want to consider getting another kitten so that she has a companion when you are off galivanting with the doggie. (Who I am sure makes a fabulous traveller. )

Is Meadow declawed? If so, how long ago?