Is it normal to have palpitations and tremors after nebulizing?

Some times. Yes I am presuming you are using a alpha agonist agent like albuterol and this can cause some of the effects. Suggest speak to your long doc and get dose adjusted. If you are not using albuterol then need work up. How this helps.
Yes. Catacholamine levels high that can cause tachycardia and - (palpitations) Very common if symptoms are severe see the pul. Doc to reasses and change medicines.