clean carpet after semen

“Dear brother I was state of janab and my underwater had few drop of urine. Since wet semen come contact with underwater. I was my thigh and legs and backside. I think during wash my legs my private parts will also became pak. When I went to dry I clean my private part with towel now I think I became najis. Because semen on private part and touch underwater which had dry urine. Should I wash towel and rewash my legs and every things. Also I have wipe face and hands with that towel.”
Also brother one of my question I said that najis tissue fall on carpet and can’t see stain also I don’t know where exactly the tissue fall. Also wiping with wet tissue will be enough, I don’t know wether someone would have touch it wet feet or not what should I do with that problem.