Synthroid dosages

I just started Synthroid 50 mcg a week ago. The only side effect I really noticed was insomnia and it was tolerable at first. By the end of the week, it wasn't any better and thought I should ask my doctor. She looked at my TSH again of 4.26, on a scale of 0.5 to 5 (for years my TSH had been around 1.5 so 4.26 is high for me and have LOTS of symptoms) and said to stop taking it that my thyroid was in normal range. I feel SO many symptoms and don't want to stop but maybe just need to adjust my dosage. I talked to my previous doctor where we used to live and she said to stop the Synthroid for a week, then start again at a lower dose of 25 mcg each day or 25 mcg every other day. Has anyone else had any symptoms related to insomnia and did a lower dose help that? Thanks!