If you want to simulate just the film without any bowl, use the surface created in the example I provided for the bowl and assign film material properties to it.
Use a Static Structural model to simulate the change in pressure. If you don't have any material creep properties in your model, then time is not real, it is just a way to meter out changes in loads. Therefore, you can ramp the pressure up to one value in 1 second, and change it to another value that ends at time = 2 seconds.
But it sounds like you expect something to change as it sits there, which implies you want to model creep. For that you need creep properties to be added to the material in Engineering Data. Once you do that, time becomes real in Static Structural and to simulate 5 days, you set an end time of 5*24*60*60 = 432,000 seconds.
There are many creep models that you can read about in ANSYS Help under the Mechanical APDL, Material Reference manual.