Am I late due to pregnancy or stress?

Patient: About two weeks ago I put my dog to sleep because she had terminal cancer and it came on quickly. It was both very sad and stressful. My periods come like clockwork (period tracker trying to get pregnant). It comes on the day it is due at 11 pm every time but this month I am 8 days late. I have had at least 5 negatives within these 8 days and I have no idea what is happening. I do have hypothyroidism but I have been diagnosed for three months now and I am on Synthroid 112 mcg. I was diagnosed about 2 years after my son was born. Could I be pregnant or is it stress?

Symptoms: I am nauseous, have food aversions, tired, moody, late, some cramping. I do not have breast anything (sore, tender, heavy, etc.), no spotting, no darkening of the areolas