jellybean,
I hope this doesn't sound too non-specific but symptoms and changes in TSH level varies among patients who experience the onset of Hashimoto's autoimmune thyroiditis, that results in hypothyroidism.
Some patients have highly elevated TPO and or TG antibodies when Hashimoto's is detected but their TSH is normal and they have not begun to experience symptoms of hypothyroidism. Other patients might start experiencing symptoms with TSH only mildly elevated, in fact I've read the testimonies of patients needing treatment even with TSH only at high-normal or only slightly above normal.
A good thyroid treating Dr. will monitor both symptoms and TSH and other thyroid function levels because of the variables among patients.
That's kind of a broad answer but a hard one to narrow-down with patients having such individualized experiences with this disease. I hope that answer helps a little!