Re: My dilemma...
It depends. Nothing with thyroid is emergency. You could wait until the next semester is over. Or you could wait for certain things to come out at a better time for you.
First, I don't know why they sent you for nuclear scans---they are really of the past. It's really almost irrelevant if you have cold or hot nodules in terms of size. If your blood work is okay, it's more important to get a needle biopsy on any larger ones.
If you decide you need thyroid surgery, it is an overnight deal (because they have to monitor your calcium levels). If you are on thyroid meds already, it's not a big deal. If you aren't there might be some blood work adjustment period.
It's good to baby yourself for a week or so after surgery. So right before a break is a good time to schedule it. If this proved to be thyroid cancer, which I doubt, and you determined you needed RAI afterward, you could delay that for the summer, so if you had to be out a week or so you could do that easily.
I had an fna that was positive for thyroid cancer, and I scheduled my surgery for 2 months later because I had a vacation scheduled---it didn't impact anything.
Take your time to find a really great surgeon, don't panic and rush. Do what you need to do.