@ddon My port was very tender for a few weeks. Then it became just uncomfortable for a long time - felt heavy and I was unable to sleep on that side as the compression would cause some pain so slept on my back for months. It settled down about the same time as I stopped needing it, from memory. However, I am still extremely glad that I had it as, once it was working properly, it took so much of the difficulty away when getting treatment and it means that my veins have held up which was pretty important to me given the other arm is not usable.
I would suggest that you mention it to your doctor and certainly to the nurses when they come to jab you - they need to know about it even if for no other reason than to take extra care not to hurt you. You can get numbing cream to apply before treatment if you need to but I never used it and was fine.