Hi, I Have Been Taking 25mg Of Amitriptyline For Mild

hi, I have been taking 25mg of amitriptyline for mild insomnia and migraine nightly for 12 years. I feel I have been taking this drug for long enough now and I still get occasional migraines and still wake very early in the morning so i have recently stopped taking it by alternating the nights that I take the dose. I haven't taken it at all for around two weeks now, I am waking nightly around 4 am but can usually get back to sleep eventually but I am scratching my back, upper arms and legs in my sleep and constantly itching during the day, could this be a side effect of withdrawing from the drug? I would appreciate your professional advice thank you