Severe COPD patient, now developed hand tremors. Trouble sleeping, when does sleep not feel refreshed. Frequent headaches. Poss cause? Linked 2 copd?

Med induced. Beta agonist therapy in inhaled therapy may induce tremors. Also severity of COPD can also contribute with associated muscle loss. Sleep is unrefreshed probably by sleep apnea which is fairly common in copd. A sleep study and treatment with CPAP or bipap may help.
Blue Puffers. Yes. This is most likely linked to the lack of good oxygenation, too much carbon dioxide and carbon monoxide and the sensation of suffocation that goes along with this severely dangerous condition.