Talk to Psychiatry on Weak Mussels

I have type 1 diabetes but it's controlled now, as for insulin I take Humulin R not regularly but I am having very weak mussels through the body, especially my shoulder muscles. I also have some pain in my shoulder. During exercise or after exercise I feel a lot of pain in my leg and also my muscles sheevrin when I do exercise ( cardio exercises) so pls tel me what should I take or do tests