Main thing is to obtain the pathology report which gives detailed information about possible margins and whether it was fully contained. It will also determine the extent of cancer and whether there were any more agressive Gleason scores than indicated in the pre-surgery biopsy.
All of this will help determine the prognosis, and probability of any additional treatment being required at some point.
It takes some time for pre-surgery PSA to leave the system, so it's usual to have the first PSA test six weeks after surgery.
Recently viagra or similar is used soon after surgery to assist the blood flow and healing process. Do not take the large dose 100 size often prescribed, as that can cause problems. Cut them into 4 or obtain smaller size pills to start with.