In my opinion, not necessarily, but it could be, YES.
Of course, that most likely means that there is DEFINITELY "SOMETHING" there, whatever that is. DO NOT ignore it.

Most symptoms you describe are typical of a pesticide poisoning. These include the following on your list:

Twitchy muscles
Fatigue
Sudden leg movements in bed at night
Reactive hypoglycemia if I don't eat protein with each meal
I can't breath very well
Tingling in different areas of my body
Mood swings

How could you get a large dose of pesticides in your system? This could be applying Frontline or that other brand of flea medication on your cat. You should use gloves and avoid petting your cat for a few hours aferwards. I knew a woman who suddenly developed these very symptoms after accidently absorbing a drop of flea medication through her skin. It took her about a month+ to get over it.

Vitamin B6 and B1, plus magnesium with calcium and vit. C with other antioxidants should help you clear the pesticides out of your system. And yes, protein with every meal. Read about the pesticide poisoning on the net. B6 and magnesium are a must.

If it is not your pet flea medication, consider other pesticide sources in your environment. Perhaps your landlord or a neighbour had a pest problem and treated it without letting you know. Look around.