Are you suffering from delusion
of parasitosis, a psychiatric condition in which the affected person develops a strong unshakable belief that worms are creeping beneath my skin. They keep crawling all the time with stinging from within. You always wants to to get rid of these hidden worm in your body by scratching & trying to catch them alive but up to now both are not successful, either you have not get freedom from these sensation or have not get the worms in your hand. You should visit a psychiatrist
for its evaluation. Pimozide
is a specific anti-psychotic for this condition that benefit a lot.
 Are you suffering from scabies
, a skin infection
in which the real tiny insects makes their niche in the very superficial layer of skin. They do crawl, sting, scratch & sometime comes out of their burrow on to skin surface. Keep trying to hunt them alive but better to use scabicidals after visiting professional like Skin & VD expert for early evaluation & early treatment as this condition is contagious can affect whole your family.
 Are you suffering from depression
with prominent parasthesia in which normal sensory perception is altered so much that it gives you feeling of crawling worms like body movement. But again you need evaluation by a mental health experts for this ailment . If the case is like this, I will like to prescribe you Amitriptyline
for these particular situation of depression with strong sensation of worm like body movements.
Thank You ( Viewer rating for my Answer is awaited)