Cytomel comes in different dosages, just like other medications, so just saying you went from 2 to 1, isn't enough. Your cytomel pills are 5 mcg ea? No, cytomel does not come in smaller doses than 5 mcg, but some people have been successful splitting the pills.
When you were taking 2 pills/day -- did you take them both at once? Many of us find that splitting our dosage into multiple doses, works best.