Levothyroxine Sodium and hypothyroidism

Started taking Levothyroxine 100 3 weeks ago, for last week I'm in agony, my joints and muscles are sore, specially legs and arms, got constant headaches, mood swings, I'm also short of breath which developed before muscle pains, went to the doctor, was told it's probably asthma (!!) got tablets and inhalator and he mentioned anxiety, when muscle pains started, went back, was told that it's not related with hypothyroidism or Levothyroxine, it's a virus (??) have to drink plenty of water and got Diazepam and link to anxiety website. Help, it's not stress related! I don't know what to do!! Does anyone know how to get rid of those pains?

hypothyroidism- since August 2007
I went for a second opinon and he started me on Levothyroxine .50 3months later increased dose to .75.

I have put on some more weight, losing my hair, but I am sleeping better, this has helped me with my panics attacks, and I have little more energy.
I can not complain. I know it takes time to get it right.

i have just been diagnosed with auto-immune hypothyroidism and have been prescribed 25-Eltroxin sodium. I've also been trying to conceive. At the time of starting my medication I was coming up to ovulation. On day 13/14 of my cycle I was worried as I noticed significant breakthrough bleeding (bright red/with clots). I am waiting for my temperature to go up to show that I've ovulated but it hasn't happened yet. My bleeding is lighter now, 5 days on and brown in color. Can anyone explain how/if thyroxine can cause this as I've never had mid-cycle bleeding before. I have been bleeding for 4 to 5 days now and its not as heavy as it was. What is happening to me?