Hi
I had a PICC line too, after it took them 3 attempts to find a good vein for my first chemo.
Going in, it hardly hurt. The needle is similar in size to the one for giving blood, but, like supertrouper, I had the numbing cream. It did feel odd as they threaded it through - not painful though.
For a couple of weeks afterwards, I had phlebitis, where the vein swells in protest. It felt a bit like a pulled muscle. Treatment was heat (i slept with a hot water bottle on it) and ibuprofen. After the 2 weeks it was alot more comfy. The arm was still a little stiff, but not bad.
The other bad effect I had was a mild reaction to the water-resistant dressings. I had the line in for 13 weeks, and it took 5 weeks for the itching to get bad. The chemo nurses then found a better one that I didn't react to, but because you don't get any air to the skin, it didn't heal properly until I had the line out. I wish I had mentioned it sooner, as then the dressing could have been improved sooner.