Hi Richard - mine hurt like a son of a gun but only for 3-5 days. "Digging" does not sound like a good thing at all and I can only imagine that would contribute to the pain. If you're at an 8/10 WITH the fentanyl patch then you are not getting adequate pain coverage.
Like Christine suggests - time to discuss better pain management.

Sorry you're having these complications - the porta-cath is supposed to help in these situations not contribute to the issues!