cleaning urine

assalamualaikum, i am in my mid teens and i accidently urinated on the carpet, washed it a few times.left it to dry but about 15 minutes my mother walked over the capet while it was drying, and maybe my brother and sister did aswell. I didn’t tell them and i still haven’t due to fear. when their feet or socks got wet a bit and walked around the house with them, put their feet on chairs, sofas, beds, has all that become impure. do I have to wash all these. and when i touch things touched by their feet am i impure. and all the things i have touched are impure? i don’t know what to do, i wasn’t thinking about the consquences. At the time i urinated the carpet, i thought washing it was enough and after washing it you could walk on it and no impurity would be on me. the next day i learned about najiis and how to clean them. I am ashamed about this, and want allah to forgive me for this, and inshallah i will never do this again,
also, if something such as carpet, clothes that get impurities on them and they are left to dry is the impurity gone? can i touch it and still pray and read Quran or does it have to be washed. i feel as if everything is impured and need to be washed.