I had this two years ago.
I was diagnosed as having a multinodular goitre.
The needle test is a little bit grim, but over very quickly.
Most likely it will be clear and if it is a mng then my understanding is that they subside.
In my case there were cells in my needle test that were... not undefined, but the medical equivalent.
So my needle test wasn't clear and there was the possibility it was a cancerous tumour.
I was offered further needle tests to see if they were clear (as it wasn't certain that there was anything to worry about) or surgery to have half of my thyroid gland removed. This was the only way to know for sure whether it was cancerous once the needle test was inconclusive.
I opted for surgery and it turned out I had a follicular adenoma, which is a benign tumour.
I was very scared and worried, but a friend who had thyroid cancer told me that the very worst outcome was very treatable.
Have my first ever (hug), it's frightening, but the chances are good that your needle test will be clear and you won't have to think about it any more.
I'm happy to answer any other questions you might have if I can help at all.
Best of luck :)