**** coming out from the shower and toilet ?

So I live in the house complex kinda like a town home and we been having a problem resently when ever something uses water like the shower or the toilet water usually gets cloged but I unclog it with hot water and baking soda so now when ever we use the washing mashine the shower gets filled with nasty nasty water and with little chuncks of **** I threw up right after I saw that cause it's so gross and the toilet was doing the same thing from the hole the water leaves it was coming in and I don't think that's any of my **** I think it's actually other peoples **** so what should I do should I tell the manager about what's going on should I call a plumer or is there a fix fror my problem ??