Quick info from a doctor:
Any new or revised wound is best kept dry or protected from water by a dressing for 48 hours. After that the clot is sealed and basically waterproof.
So shower is ok. Keep dressing on during shower. If there appears to be water under dressing afterwards, change the dressing for a clean one. Can remove dressing if wish after 2 days, but 4 to 5 days is more usual as wound may weep a bit on to clothes. Remove dressing at the earlier date if you have allergies to adhesives.
My port was very tender for a couple of weeks. I swear they put it in with a sledge hammer. Now it is just fine and I'm very glad I had it put in. I use a tube of sheepskin around the seat belt in the car when driving to lift the belt away from the port site.
Good luck
