If you just had your port placed yesterday it’s pretty normal to have tenderness around the port and all the way up in to the neck. Where the port was implanted is an opening made into your skin. So think of it as a wound that takes time to heal. Also the little protective ring around that opening, supporting the lumens, puts pressure on that area directly so can make it a little more sensitive.
It may start it itch as well as the area starts healing. Don’t scratch it! Just use your hand to pat it.
I used to react to the clear protective patch placed over my port, getting raw and irritated. When the patch got replaced weekly, my nurses went to another type which wasn’t reactive. It used different adhesive. So if you have any issues like that don’t hesitate to tell your oncology team.

The area up into your neck will feel very odd for a few days until you get used to it. This all becomes second nature after a week or so. I felt like an alien from a sci-fi movie. But you’ll be grateful for the port as your treatment begins. Fewer pokes and all your meds, blood draws, etc., come right from the lumens, not your arm.

I am sorry that you’re needing a port. This sounds like a new journey you’re about to enter. May I ask what you’re needed chemo to treat?