Been using propranolol for anxiety with a slight problem..?

I take 40mg of propranolol twice daily for anxiety (GAD) and its been a life saver! The only problem I have is it causes me some breathing problems. anyone know what i can do about it? also it causes me to have insomnia? like impossible to fall asleep! anyone get this? it is a life saver and I am not stopping this but need help with these problems.