Sexual OCD or frequent nightfall. Chair!

I have a problem with semen/sperm contamination and spreading that contamination around.If I have a wet dream or if I commit a mortal sin of masturbation, I feel that things can get contaminated with sperm/semen. [However, I feel more concerned with sperm/semen contamination as a result of mortal sins of masturbation than as a result of wet dreams (as I can't really control wet dreams)].For example, stepping on a contaminated spot by mortal sins of masturbation. If I step on a contaminated spot on the carpet, my socks would be contaminated, and then everywhere else I step after stepping on the contaminated spot would be contaminated too (unless I changed my socks after stepping on a contaminated spot).Another example is when I have a wet dream, my bed becomes contaminated, and then if I sit on the couch after getting out of bed, the couch would then be contaminated, and if I sit on a chair