Armour Thyroid and Long Menstrual Period

I was diagnosed with Hashi's at 34, and have been able to maintain a steady weight (30 lbs over ideal weight); at 40 and in the span of 10 months, I've gained an additional 20 lbs, and my doctor gave the usual answer...age, lack of exercise, follow low-sugar diets.  Last month I asked for Armour Thyroid rather than Synthroid, and I'll get retested in 1 week for results.  Initially, I thought it suit me well, but I noticed that I started my period 1 week early and have been on my period for 10 days.  Typically, it lasts 3 days.  I will relay this to my doctor next week, but should I be alarmed?

Thanks.

[Mark Lupo, M.D.]

would not be alarmed - it may take some time to titrate the dose.  

the weight issue is tough - it's likely more diet/exercise than thyroid....