Constipation post surgery is quite common after surgery. First of all are you hydrating really well and second are you taking any kind of stool softeners. I took a stool softener throughout my recovery.
However, even with a stool softener I had one bad bout. Some of the recommendations are prunes, prune juice heated up and also pumpkin puree (NOT pumpkin pie filling). I think I tried all of the above as well as apples. I did resort to Miralax finally and with all of the above it worked. After that I concentrated on staying hydrated, took my stool softeners and ate prunes regularly.
I hope you find relief soon.