Re: possible thyroid cancer
First, what kind of doctor have you been seeing, an ENT? An Endo? That would make a big difference.
Second, the only thing an uptake scan can tell you is if a nodule is "hot" or "cold" if yours was "normal" then that does not mean cancer, a cold nodule has a slightly increased chance of being cancer (about 5% more). A nodule has a 90% chance of being benign---no matter what that dr, told you.
Most of these nodules are benign, and they often don't know until it's removed.
After the ultrasound, the will do a needle biopsy, and I wouldn't worry at all until after you get those results---it's a while off, now you have to take this one day at a time, and keep yourself busy, so your mind is off it.
In the absolute worst case, if it's cancer, most thyroid cancer is curable, and pretty easily......I had it 3 years ago, and my surgeon says I have a greater life expectancy than a sibling who never had it.
You are going to be just fine!