The next day of my allergy shots i feel a little more tired/congested, is it caused by the allergy shot or the 'singular' that i take?

Pls tell ur doctor: or your allergist who precscribed the allergy shots, that can happen during the build up phase, if you are in the begining of a cold, with a new vial of the maintanance concentration, usually a mini history is taken prior to every shot and as well peak flow measurenent,, your doctor would adjust the dose accordingly, pls keep taking your meds as prescribed, those symptoms would resolve soon,

M.D. visit/Mgt: It is not likely to be due to the Singulair (montelukast). Since you have nasal allergic disease under treatment with inhaled steroids and difficulty breathing, reviewing your allergic triggers and a follow up appointment is needed. I would suggest a pulmonary function test with and without a bronchodilator.