In my personal experience, it's normal. It was the second week of my dose that it did this to me. It was always worse at night but significantly better during the day (usually). I also had some neck stuff going on at the same time as this... it would feel 'stuck' around there (with some pulling) when I moved a certain way (from under-jaw down) but that's because some of the muscles and whatnot in there had to stretch to accommodate the enlarging of my entire larynx and my trachea as well. When those finally did get pushed over and out, that stopped. If memory serves, the pain in my larynx stopped around the seventh month. It still happens occasionally but nowhere near as intense as it had been happening from around the third month on (basically, it felt like my throat was being bloated out {think of a buoy being overinflated, that'd be about right} but it really wasn't. That had to be the thickening and stretching of the actual cartilage of the larynx. That also changes, not just the vocal cords/muscles in the middle of it).
I did go to my doc about it and after palpating around, declared it normal. But that's me. It's never a bad idea to get it checked. In the meantime, try warm/hot drinks. For me, the only stuff that helped was coffee (tried tea and whatnot, didn't really do anything for mine). Your mileage may vary. Find what works for you.