I take a thyroid pill for over 2 years, lately I have been very anxious?

I am a nurse and I draw blood, all of a sudden I have become vvery anxious about drawing blood and I dont know if it is related to taking thyroid medication. I think I want to stop taking it to see if my anxiety decreases, but I have read that too low of a level can also cause palpatations and anxiety.This anxiety only manifests when drawing blood. It could also be related to a patient that got very upset with me 4 weeks ago after I drew his blood, I dont know if he has caused me to be apprehensive about drawing blood. FYI-- I have drawn blood for over 18 years and I am considered one of the best in my agency, but all of sudden I have become extremely anxious. the last 3 patients I was a wreck. Please help, is the thyroid medication or did that patient cause some sort of psych damage.