2000 Oldsmobile Alero iM so frustrated with my car

Well I took my car in for an oilchange and thats wen they told me I had a leak my antifreeze was leaking out so they put it on the machine and told me that it was my water pump water pump housing and a timing assbemly kit and I had to replace theromstat and gaskets and also heater hose so I had them to replace all that and I get my car back and its making some noise and my car was not making that noise wen I took it in and so I took it bac and now there saying its the timing turner and it had to be changed do to all the work above done on my car so I then went and get the timing change tenear done on my car and its still making the noise on the passager side of the vechile under the hood and now there saying it could b the oil pump and I dont understand how cause my car was not like that wen I took it in and now it has went from a leak to an oilpump it seems like its going from one probelm to another please help me out cause I feel like they have made some errors and I paying for there mistakes.