Thanks for your all your advice on this.
I looked at the output file and all of the cells were dry so that was probably the issue and why no head file was created. I am trying to redo this model and am running into other issues. The whole area is rather thin, 40m thick, and 3300m wide. The whole area is covered by clay till and underlain by clay till with two sand and gravel aquifers in between that are separated by intermittent clay till layers. The west and east sides of the model are constant head boundaries and the north and south sides are no flow boundaries. I have recharge over