Getting Tired, Short Of Breath, Skin Feels Dry, Flu Like Symptoms. Missed Thyroxin. Is This All Related ?

I noticed I was getting tired short of breath, my skin started to look and feel very very dry specially on the scalp. I am a senior high teacher (62yrs old) and have been on thyroxin now for 15 months (about 75 ug per day) We have had lots of stress , changes and trauma in the family in recent couple of months. Birth, death, christening, relocation. I found I could hardly walk from my car to class or even between buildings. I can't stand over 15 minutes I feel like there's nothing left in the tank. I also had flu symptoms, coughing badly, head ache fever etc. these last couple of weeks. And in all this turmoil I missed my thyroxin tablets suddenly like they were never there. I have never missed any before this. I believe I have not taken one for about 2 and half weeks. Everyday had family stress challenges and my own illness and somehow the taking of thyroxin completely vanished out of my head. I am home sick today from work and when I had a quite moment to reflect on why I feel like I just can't go on and function another day I suddenly remembered that I had stopped taking my thyroxin.
Now I am worried on how all this has and will effect my health. Is this normal to feel so badly.